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  • 1980-1984  (207)
  • 1980  (207)
  • Ultrastructure  (122)
  • Rat  (88)
  • Nuclear reactions
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Development genes and evolution 188 (1980), S. 65-73 
    ISSN: 1432-041X
    Keywords: Nuclear migration ; Cleavage ; Microtubules ; Ultrastructure ; Gall midge
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary In the eggs ofWachtliella persicariae the cleavage nuclei move relative to the surrounding ooplasm. This ‘active’ migration is caused by an organelle whose ultrastructure was studied throughout the mitotic cycle. It consists of a greatly enlarged polar cytaster derived from the mitotic apparatus, linked to the nucleus by 100 Å filaments. The microtubules of the cytaster were found only during periods of active nuclear migration, i.e., from the onset of anaphase to the early prophase of the next mitotic cycle. They are always solitary and follow the course of the astral rays, which are known to temporarily adhere to peripheral structures of the egg cell and to exert tractive forces. In contrast to the cytaster microtubules, the microtubules in the spindle are bundled and persist from early metaphase through late telophase. During ontogenesis the first migration cytaster is built up between 3 and 12 min after oviposition near the anterior egg pole, in the vicinity of the sperm nucleus. In non-inseminated eggs time lapse films show a migration cytaster to develop autonomously in a region free from nuclei, but it does not follow the normal path of the male pronucleus. In several cases the female pronucleus, which remains without a cytaster of its own, was observed to move to the cytaster generated in the absence of the male pronucleus. Whether or not it is adhering to a nucleus, the cytaster divides into two at the correct time, i.e, corresponding to the first cleavage division in fertilized eggs. In some non-inseminated eggs this type of ‘pseudocleavage’ has been observed to occur repeatedly, giving rise to an increasing number of anucleate cytasters.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Development genes and evolution 188 (1980), S. 163-177 
    ISSN: 1432-041X
    Keywords: Yolk sac ; Ultrastructure ; Embryogenesis ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Changes at the ultrastructural level during germ band extension in the embryo ofDrosophila melanogaster are described. Cytoplasmic connections between cells and the yolk sac are present during initial cellular movements. At this time, a continuous system of microfilaments is present adjacent to the membranes in the connections and at the periphery of the yolk sac. As germ band extension progresses, this system becomes discontinuous, and microfilaments are apparent only in the immediate vicinity of the connections. Cytoplasmic connections are disassembled at approximately the midpoint of extension; at the same time, extensive membrane associations develop between germ band cells and between these cells and adjacent yolk sac membranes. Positioning and orientation of cytoplasmic connections suggest that the yolk sac, via these connections, is actively involved in the cellular movements of early germ band extension.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 160 (1980), S. 275-284 
    ISSN: 1432-0568
    Keywords: Adenohypophyseal rudiment ; Follicular cells ; Ultrastructure ; Culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The epithelial rudiment of 4 day-old quail embryo adenohypophysis, cultivated in vitro under conditions allowing glandular differentiation, displays peripheral cells that progressively acquire follicular cell features. They elongate, develop numerous microvilli, junctional complexes, interlocking membranes and bundles of microfilaments. These follicular-like cells derive from peripheral epithelial cells that, in situ, become glandular. These results show that follicular cells can develop from undifferentiated cells. They undergo this pathway of development, in all likelihood, as a result of perturbations in their microenvironment.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 158 (1980), S. 349-360 
    ISSN: 1432-0568
    Keywords: Afferent neurons ; Hypoglossal nerve ; Rat ; HRP-tracing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Cell bodies of sensory neurons of the rat's hypoglossal nerve were demonstrated by the somatopetal horseradish peroxidase (HRP) transport technique. Labelled perikarya were found within the second and third cervical spinal ganglia and in the vagal sensory ganglia. After application of HRP to the cut peripheral trunk of the hypoglossal nerve about 200 labelled cell bodies were counted in each animal. The vast majority of the axons from cervical spinal ganglion cells reach the hypoglossal nerve via the descending ramus (N. descendens hypoglossi). However, there may exist an additional pathway, probably via the cervical sympathetic trunk. Application of HRP to the medial and lateral end branches led to a labelling of much fewer spinal ganglion cells while the number of labelled vagal sensory neurons remained unchanged. Thus, it is suggested that the majority of the cervical afferents of the hypoglossal nerve originates within the extrinsic tongue musculature and the geniohyoid muscle, whereas the vagal afferents may perhaps derive exclusively from the intrinsic muscles. Histograms of the mean diameters of labelled cell bodies show a predominance of very small perikarya. This contrasts with the diameter distribution of sensory perikarya labelled after HRP application to nerves supplying other skeletal muscles. It is therefore assumed that the afferent component of the hypoglossal nerve is composed mainly of small-calibre axons.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 159 (1980), S. 59-69 
    ISSN: 1432-0568
    Keywords: Infrahyoid muscles ; Motoneurons ; Spinal ganglion cells ; Axons ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Perikarya of motoneurons and spinal ganglion cells attributed to infrahyoid muscle nerves of the rat were labelled by retrogradely transported horseradish peroxidase (HRP). For the differentiation of motor and sensory axons cross sections of the nerves were stained for acetylcholinesterase. Numbers and diameter distributions of perikarya and myelinated axons were determined. Motoneuronal perikarya innervating the infrahyoid muscles are located from the transition zone brain stem/spinal cord to the segment C 3. They are found mostly in the medial part of the Rexed laminae VII and VIII at the level of C 1 and C 2 and more ventrolaterally in C 3 and are therefore located to a large extent in areas until now not recognized to contain motoneurons. Our results provide evidence for a somatotopic organization of the motoneurons in the upper cervical spinal cord. The diameter distributions of motoneuronal perikarya and axons are in most cases bimodal, the two modes corresponding to α-and γ-motoneurons. In relation to the diameters of their perikarya α-axons are significantly thicker than γ-axons. In contrast to the motoneurons no clear correlation could be established between the sizes of perikarya of spinal ganglion cells and their peripheral processes.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 159 (1980), S. 277-288 
    ISSN: 1432-0568
    Keywords: Megakaryocyte ; Bone marrow ; Steel mice ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The megakaryocytes in the bone marrow of steel mutant mice (Sl/Sld) and their normal littermates (+/+) were studied by light and electron microscopy with special emphasis on their maturity and distribution in the hematopoietic cords. A higher percentage of megakaryocytes lying against the sinus wall, a higher percentage of the sinus perimeter covered by megakaryocytes and a higher percentage of large megakaryocytes were found in Sl/Sld mice than in +/+ mice. In addition, more large megakaryocytes as well as senile megakaryocytes were observed in the spleen of Sl/Sld mice than in that of +/+ mice. These observations suggest that more platelets are produced in Sl/Sld mice than in +/+ mice on the basis of per unit area of the marrow tissue. Heretofore, the fate of the senile megakaryocytes in the marrow was not known. However, in Sl/Sld mice senile megakaryocytes were often found entering the marrow sinuses from the hematopoietic cords. They were also seen in the lung and the spleen where degradation of senile megakaryocytes was observed. These observations suggest that senile megakaryocytes in Sl/Sld mice leave the marrow and are removed by the reticuloendothelial system outside the marrow.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 158 (1980), S. 167-178 
    ISSN: 1432-0568
    Keywords: Placenta (human) ; Villous stroma ; Intercellular junctions ; Endothelium ; Ultrastructure ; Freeze-fracturing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Intercellular junctions within the villous stroma and the cytotrophoblastic layer of the human full term placenta were investigated using thin sectioning and freeze-fracturing. Numerous maculae adherentes (desmosomes) were found between the cytotrophoblast cells and the syncytiotrophoblast. This junction type was also seen connecting adjacent cytotrophoblast cells. Large gap junctions were frequently observed in contact areas of perikarya or at processes of adjacent fibroblasts. They often exhibited a peculiar pattern of their particles on the P-face of the membrane. Small rows of junctional particles were found on the P-faces of interconnected smooth muscle cells and gap junctions frequently bridged myoendothelial and interendothelial contact zones. The significance of the junctional complexes is discussed in relation to functional systems within the villous stroma of the human full term placenta.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 160 (1980), S. 11-27 
    ISSN: 1432-0568
    Keywords: Sertoli cells ; Rat ; Fetal and postnatal life ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Sertoli cells have various functions: mechanical (creation of two compartments in the seminiferous tubules, migration of germinal cells), secretory (secretion of anti-Müllerian hormone, inhibin, androgen-binding-protein and estrogen) and phagocytic. We report an ultrastructural study of the rat Sertoli cell during maturation and consider possible correlations between the acquisition of certain morphological characteristics and certain functions. During fetal life, the Sertoli cell possesses differentiated zones of junction with the gonocytes and seems to have a role in the migration of the gonocytes towards the periphery of the seminiferous tubule. The Sertoli cell performs the phagocytosis of the gonocytes which degenerate during their migration, and seems to be the site of production of protein granules, whose presence can be related to the synthesis of anti-Müllerian hormone. After birth and before puberty, when the inclusions resembling secretory granules disappear, the Sertoli cell membranes in contact with spermatocytes II and spermatids differentiate, forming, through the differentiated junctional complexes, two compartments (adluminal and luminal) in the seminiferous tubules. Finally, they acquire the characteristics of active secretory cells, capable, in particular, of steroid synthesis.
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 160 (1980), S. 239-252 
    ISSN: 1432-0568
    Keywords: Liver ; Innervation ; Adrenergic nerves ; Guinea pig ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The adrenergic innervation of rat and guinea pig liver is investigated using the glyoxylic-acid — paraformaldehyde method for fluorescent microscopical demonstration of adrenergic nerves and electron microscopy. The nerve distribution in the parenchyma of both animals is compared. The distribution of the liver nerves as detected with fluorescence microscopy is confirmed electron microscopically. The two species exhibit fundamental differences in their liver innervation: (1) In the guinea pig, a rich innervation is found in the trias as well as in the parenchyma. Many nerves traverse the entire liver lobules and may end near the central vein. The guinea pig hepatocyte innervation seems to be uniformly adrenergic. Electron microscopy shows that the varicosities of these nerves mostly form close contacts to the hepatocytes but also to other hepatic intralobular cells. (2) In the rat, the liver nerves are as a rule restricted to the triads, running mainly with smooth muscle containing blood vessels. It rarely happens that nerves penetrate into the lobule and come into contact with the peripherally located hepatocytes.
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 159 (1980), S. 289-305 
    ISSN: 1432-0568
    Keywords: Placenta (rat) ; Development ; Intercellular junctions ; Ultrastructure ; Freeze-fracturing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The differentiation of chorionic layers II and III and alterations of intercellular junctions within the developing placental labyrinth were investigated in rats. Between the 14th and 16th day of gestation, the trabecular structures of the labyrinth alter and increasing numbers of primary, secondary, and tertiary lamellae develop. Trophoblastic layer I remains multicellular. Layer III rearranges and cytoplasmic fusions result in a continuous cytoplasmic barrier intervening between the already syncytial trophoblastic layer II and fetal capillaries. Simultaneously, most of the “undifferentiated” cells within the labyrinth disappear. Thin sectioning anf freeze-fracturing reveal multiple images of intercellular junctions, particularly gap and tight junctions in the cellular and syncytial parts of layers II and III. Continuous and regularly arranged tight junctions occur as well as fragmented structures which are spaced irregularly. Gap junctions are occasionally found between the juxtasinusoidal regions of layers II and III on the 14th day. More often they occur within restricted areas near the center of the trabeculae, integrated within extensive tight junctional strands. Gap junctions increase in later stages of pregnancy and eventually become distributed between the interfaces of layers II and III in the primary lamellae.
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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 50 (1980), S. 227-232 
    ISSN: 1432-0533
    Keywords: Wallerian degeneration ; Schmidt-Lantermann incisures ; Glycogen clusters ; Peripheral nerves ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Phrenic and sciatic nerves of the rat were examined during the initial stages of Wallerian degeneration 4–48 h after axotomy about 5 mm below the level of transection. One of the first changes observed in transected axons was the appearance of glycogen granules and formation of clusters of particulate glycogen at the Schmidt-Lantermann incisures and at the nodes of Ranvier. Four hours after transection, glycogen granules were found at these sites mainly attached to the tubules of axoplasmic reticulum or dispersed in small clusters in the axoplasm. At later stages, glycogen particles increased in number and formed elongated clusters arrayed mostly longitudinally among axonal organelles filling stretches of axons about 2 μm long adjacent to the incisures and in nodal regions. The buld-up of glycogen clusters reached a peak at 22 h after axotomy, when longitudinal arrays of glycogen particles were found at about 70% of the incisures and nodes examined. The percentage of these sites containing glycogen clusters had already decreased 26 h after axotomy. When axonal degeneration advanced and axons contained only floculated material and swollen mitochondria, glycogen granules also disintegrated. It is of interest that glycogen particles accumulate in those regions of the internode where the axon will soon become disrupted during ovoid formation. The possible mechanisms leading to glycogen accumulation at these sites are discussed in relation to the active role of Schwann cells in Wallerian degeneration.
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  • 12
    ISSN: 1432-0533
    Keywords: Skeletal muscle ; Senescence ; 65 to 89-year-old people ; Histopathology ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Biopsies for histochemical and ultrastructural studies were taken from the M. vastus lateralis of 45 healthy sedentary men and women aged 65–89 years. With increasing age the histochemical reactions reveal changes in the fibre type distribution characterized by a decrease in the percentage and predominant atrophy of type II fibres. The most frequent changes in the oldest subjects are: targetoid fibres, type I fibre predominance, and type grouping phenomena; expressions of denervation. Myopathic alterations are observed unusually. Electron microscopic findings are characterized by myofibrillar disorder, streaming of Z line and rod formation, and dilatation and increase of sarcoplasmic reticulum. As the age increases, the fibres become richer in intracellular lipid droplets and lysosomes. Intramuscular microcirculatory alterations, consisting of arteriolosclerotic changes and increase in width of the capillary basement membrane, are also observed and discussed.
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  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 52 (1980), S. 119-127 
    ISSN: 1432-0533
    Keywords: Hypothalmus ; Rat ; Streptozotocin ; Diabetes ; Morphology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Sixteen male Wistar rats, 1 year after injection of streptozotocin or vehicle, were fixed by whole-body perfusion, the brains were removed and processed for light and electron microscopy. Study of semithin sections from the hypothalamic area revealed changes in the arcuate nucleus and median eminence. The lesions, in comparison with controls, were subjected to a blind semiquantitative evaluation. The following changes were observed by light microscopy in diabetic rats: accumulation of glycogen (P〈0.01), degeneration of neurons (P〈0.05), hypotrophy of tanycytes (P〈0.01), and axonal changes. Electron microscopy of diabetic rats revealed that glycogen was increased in neuronal bodies and processes (axons, synapses), also in tanycytes, and glia cells. In neurons were seen: dilated and fragmented endoplasmic reticulum, degranulated ergastoplasm, loss of organelles, increased number of microtubuli, myelin figures, irregulatities in the form of nuclei, and appearance of chromatin. The tanycytes in diabetic animals were reduced in volume, had an increased nuclear cytoplasmic ratio, a reduced number of organelles, short basal processes, and almost complete loss of the apical processes. These changes demonstrate the existance, under experimental conditions, of an encephalopathy pathogenetically related to streptozotocin-induced diabetes.
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  • 14
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 50 (1980), S. 131-138 
    ISSN: 1432-0533
    Keywords: Rat ; Cerebellum ; Vessels ; Development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The adult arrangement and the development of stem vessels and capillaries was studied in the rat cerebellum. In principle, stem vessels branch and terminate at three levels: (1) the molecular layer, (2) the Purkinje cell-granular layer, and (3) the cerebellar white matter. All stem vessels are interconnected by the capillary network which is most dense in the Purkinje cell—granular layer. As in the neocortex, the stem vessels of the cerebellum are formed successively during development, so that the later they are formed the more superficial are their terminations. The formation of multiple stem vessels in the depths of fissures and sulci during both pre- and postnatal development may correlate to regional variations in, e.g., mitotic frequency or thickness of the external granular layer. The earliest “endo-parenchymal” branches are formed before the first neurons are present. Capillary growth by sprouting during the postnatal period parallels known regional differences in the timing of the neuronal maturation, e.g., increased synaptic density and oxidative metabolism. The findings in this investigation confirm and extend the results of an earlier morphometric study on capillary development in the cerebellar cortex. Although the angiogenetic factors remain unknown, the hypothesis of a link between the vascularization and the functional maturation of the brain is corroborated by the results. Knowledge of the normal vascular development seems necessary for an understanding of brain morphogenesis and for interpretation of primary pathogenetic mechanisms in various intoxications etc.
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  • 15
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 51 (1980), S. 113-117 
    ISSN: 1432-0533
    Keywords: Peroxisomes ; Catalase ; d-amino-acid oxidase ; Glial tumors ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Morphologically and cytochemically defined peroxisomes (microbodies) were demonstrated in a series of 11 human glial tumors. The cytochemical methods used were the diaminobenzidine method for catalase and a tetrazolium salt-phenozine methosulfate method ford-amino-acid oxidase. Ultrastructurally, the peroxisomes were found as single membrane limited organelles with a granular matrix. Marginal plates as well as continuities with the smooth endoplasmic reticulum could be demonstrated. Peroxisomes were found most abundantly in subependymal giant cell astrocytomas, to a lesser number in astrocytomas and least abundantly in glioblastomas.
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  • 16
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    Electronic Resource
    Springer
    Acta neuropathologica 49 (1980), S. 225-230 
    ISSN: 1432-0533
    Keywords: Human pituitary adenomas ; Tissue culture ; Cell culture ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Pituitary adenomas of 120 patients were investigated in tissue and in cell cultures. Under different conditions of culture, the biopsies revealed different rates of growth. In tissue cultures 66% of the samples could be propagated while tumour specimens explanted in cell suspensions proliferated in 80% of the cases. Attempts to establish subcultures were also more successful when specimens were put into cell cultures primarily. Further differences of growth characteristics were observed in connection with the histological types of the parent tissues. According to the old terminology cells of mixed type adenomas had the longest life-span both in tissue and in cell cultures. Considering the proliferative activity, this type of tumour could be most frequently subcultured. Concerning the relationship of different cell components of the biopsies it was proven that survival and proliferation of adenoma cells may occur without fibroblasts. The appearance of fibroblast-like cells in older cultures is a morphological manifestation of the senescence of the specific cell types. Qualitative features of cultured adenoma cells showed that on the basis of cytomorphological properties “chromophobe” samples could be separated from the other types. Cells of acidophil and mixed type growths had the capacity of developing in vitro various migratory shapes, while “chromophobe” cells did not possess this ability. The histological diagnoses made independently from cultures confirmed the tissue culture findings. Differences of in vitro characteristics correlated also with the ultrastructural features of the cultured adenoma cells.
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  • 17
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    Electronic Resource
    Springer
    Acta neuropathologica 52 (1980), S. 179-187 
    ISSN: 1432-0533
    Keywords: Medulla oblongata ; Rat ; Chlorophentermine ; Chloroquine ; Lipidosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The present study is concerned with the question of whether or not amphiphilic drugs (chloroquine, quinacrine, perhexiline) that fail to induce general lipidosis in the central nervous system (CNS) of adult rats can produce lipidosis in a circumventricular organ (area postrema) not furnished with a blood-brain barrier. Chlorphentermine known to induce general lipidosis in CNS of adult rats served as reference compound. All drugs, when chronically applied in high oral doses, induced significant perikaryal lipidosis in the area postrema. In the adjacent nuclei (nucleus tractus solitarii, nucleus dorsalis nervi vagi, nucleus nervi hypoglossi, nucleus gracilis), only chlorphentermine caused generalized lipidosis, whereas the other drugs had either limited or no effects. The present findings strongly suggest that the exemption, of most regions of the CNS of adult rats, from lipidosis induced by chloroquine and others is due to hindered drug distribution across the blood-brain barrier, rather than being due to non-susceptibility of central neurons toward the lipidosis-inducing action of the drugs.
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  • 18
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    Electronic Resource
    Springer
    Acta neuropathologica 52 (1980), S. 157-159 
    ISSN: 1432-0533
    Keywords: Neurons ; Thalamus ; Inclusions ; Ultrastructure ; Myotonic dystrophy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Intracytoplasmic cosinophilic inclusions were found by light microscopy in the thalamic neurons of 35 consecutive normal adult brains and in a case of myotonic dystrophy, but not in six newborn children, including one with myotonic dystrophy. Histochemical tests suggested a protein composition. Ultrastructurally, the inclusions were composed of stacks of parallel alternating dark and light rectilinear profiles not surrounded by a limiting membrane. Such inclusions are a virtually constant finding in the adult human thalamus and probably represent sites of neuronal protein storage.
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  • 19
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    Electronic Resource
    Springer
    Acta neuropathologica 50 (1980), S. 81-83 
    ISSN: 1432-0533
    Keywords: Cerebral neuroblastoma ; Desmoplastic variant ; Dense core vesicles ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A desmoplastic primary cerebral neuroblastoma originating in the frontal lobe of a boy who died at the age of 6 years contained dense core vesicles within the cytoplasm of neoplastic cells as evidence of neuronal differentiation. Sarcomatous transformation had occurred at the time of recurrence. At autopsy, he also had cerebrospinal and extraneural metastases.
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  • 20
    ISSN: 1432-0533
    Keywords: Aging ; Hypertension ; Blood-brain barrier ; Ultrastructure ; Blood vessels
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary This study demonstrates that markedly different patterns of age-related changes in blood pressure and body weight occur among normotensive Wistar-Kyoto (WKY) and Sprague-Dawley (SD) rats and spontaneously hypertensive rats (SHR). In addition, a variety of age-related structural alterations occurred in the walls of arterioles, capillaries, and venules of the frontal cortex. These changes include: (1) an increase in the thickness of the vascular wall by deposits of collagen and basal lamina which, in some cases, extended into the surrounding neuropil; (2) the presence of a flocculent material in the adventitia of intracerebral arterioles; (3) vesicular inclusions in perivascular macrophages, pericytes and smooth muscle cells which were labelled with i.v. administered horseradish peroxidase (HRP); (4) fragmentation of smooth muscle cells; and (5) accumulation of lipofuscin-like pigments in perivascular glial processes. The hypertensive rats exhibited these changes, but they were more advanced and more widely distributed throughout the cerebral cortex. The aged hypertensive rats occasionally had large bundles of 10 nm diameter, intermediate filaments in the endothelial cells. Whereas no change in blood-brain barrier permeability to HRP was observed in the aged normotensive rats, all age groups of the hypertensive rats exhibited increased permeability to HRP in the initial segment of penetrating arterioles in laminae I and II of the cerebral cortex.
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  • 21
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    Electronic Resource
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    Acta neuropathologica 50 (1980), S. 221-226 
    ISSN: 1432-0533
    Keywords: Rat ; Brain ; Vessels ; Prenatal ; Development ; Protein deprivation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The internal vascularization of the brain was studied in foetuses of normal and protein-deprived rats from embryonic day (E) 12 to 15. The position of vascular branches showed distinct relations to the various zones of the neuroepithelium. The possibility that various parts of the vascular system may differ in function, maturation, and morphogenetic relations to the neuroepithelium must be considered. The distinct vascular layers were therefore given names relating them to the respective wall zone. The ingrowth of straight stem vessels from the epiparenchymal vascular plexus into the neuroepithelium and the formation of vascular branches close to the ventricular system were referred to as stage I of the internal vascularization. The resulting plexus was called the deep vascular plexus of the ventricular zone. Its formation followed the same temporospatial gradients as the formation of the marginal zone. Following the formation of the intermediate zone, more stem vessels entered the neuroepithelium and a superficial vascular plexus of the ventricular zone was formed (stage II). This plexus was positioned close to the border between the ventricular zone and the intermediate zone. Subsequently, vascular branches also formed plexuses of the intermediate and subventricular zones (stage III). No “intraepithelial” vessels were seen on E 12. The temporospatial gradients in the telencephalic vesicles were caudal to rostral and lateral to medial, starting in the parts corresponding to the ganglionic eminence in the floor of the lateral ventricle on E 13. Only the dorsomedial angles of the hemispheres showed no vessels on E 15. No obvious differences were seen between the normal and the protein-deprived foetuses regarding the timing and extent of vascularization or the size and appearance of wall zones in the immature central nervous (I-CNS).
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  • 22
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    Acta neuropathologica 51 (1980), S. 65-70 
    ISSN: 1432-0533
    Keywords: Morphometry ; Glial cells ; Portocaval anastomosis ; Ultrastructure ; Corpus striatum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructure of astrocytes and oligodendrocytes was investigated in rats 10 days, 30 days, and 10 weeks after portocaval anastomosis (PCA). Cell and nuclear sizes were measured by planimetry on randomly sampled cells magnified×24,000. The volume fractions of mitochondria, glia fibrils, and lipofuscin granules were measured in astrocytes by electronic image analysis. The mitochondrial profile area distribution and oligodendrocyte mitochondrial content were likewise estimated. All PCA animals had an increased astrocyte cell and cytoplasmic area, and after correction for cytoplasmic edema all groups had an enhanced mitochondrial fraction and mitochondrial number. The mitochondrial sizes were increased in all PCA groups. The mitochondrial profile area distribution curves did not suggest more than one group of mitochondria. All PCA groups had increased fractions of lipofuscin granules and glia fibrils. The oligodendrocytes had a slight fall in cell, nuclear, and cytoplasmic area after 30 days of shunting, and the mitochondrial fraction was diminished. After 10 weeks of PCA, all changes were reversed to normal values. It is concluded that the astrocytes are the active cells in the brain metabolism of ammonium. The oligodendrocytes seem to be dependent on neuronal integrity and do not contribute to the brain ammonium metabolism. The increase in astrocyte lipofuscin granules content may be explained by a beginning neuronal loss.
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  • 23
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    Acta neuropathologica 49 (1980), S. 43-49 
    ISSN: 1432-0533
    Keywords: Rat ; Peripheral nerve ; Macrophage ; Ultrastructure ; Histochemistry ; Acid phosphatase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The cellular content of the endoneurium in peripheral nerves of normal adult rats was studied. Endoneurial cells with high light-microscopical activity of acid phosphatase were usually located close to blood vessels or near the perineurium. Cells with the ultrastructural appearance of macrophages showed the same distribution and accounted for 2–4% of the endoneurial cell nuclei profiles. These cells rapidly endocytosed carbon particles after endoneurial administration of colloidal carbon in vitro.
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  • 24
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    Acta neuropathologica 49 (1980), S. 75-78 
    ISSN: 1432-0533
    Keywords: Lamellar bodies ; Rough endoplasmic reticulum ; Purkinje neurons ; Adenohypophysis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Lamellar bodies are stacks of parallel cisternae of approximately regular spacing derived from ergastoplasm. Their occurrence was studied in various nervous and epithelial cells of different animal species in both normal and diseased subjects. This organelle appears to be, at least for some cell types, a normal cytoplasmic feature. The number of lamellar bodies increases in some pathologic conditions and when the cell metabolism is elevated.
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  • 25
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    Acta neuropathologica 51 (1980), S. 249-250 
    ISSN: 1432-0533
    Keywords: Neurons ; Mitochondria ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Ultrastructural study of the cerebral cortex and spinal anterior horns disclosed periodically repeating processes located in the envelope space or in the intracristal space of neuronal mitochondria. The alteration was observed in postmortem cases in which fixation was delayed either voluntarity or involuntarily, but was not present in postmortem or surgical specimens in which fixation was prompt. The change is interpreted as an artifact due to delayed fixation.
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  • 26
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    Journal of molecular medicine 58 (1980), S. 501-510 
    ISSN: 1432-1440
    Keywords: Primärer Hyperparathyreoidismus, klinische und klinisch-chemische Befunde ; Akuter Hyperparathyreoidismus ; Ultrastruktur ; Hypercalciämie ; Parathormonspiegel ; Primary hyperparathyroidism, clinical and laboratory findings ; Acute hyperparathyroidism ; Ultrastructure ; Hypercalcemia ; Parathormone, blood level
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary In a series of 6 patients out of 47 cases with extrarenal hyperparathyroidism we investigated the clinical, laboratory and ultrastructural peculiarities of acute hyperparathyroidism. It was found that there are characteristic differences between both entities which, however, are fluid. Clinically more severe were neuromuscular psychiatric and mental signs. In the laboratory parameters PTH determined by radio-immunoassay and calcium were higher whereas hemoglobin was lower. The weights of the adenomas did not differ in both groups and this was also true for light microscopy findings. Electron microscopy revealed accelerated hormone extrusion and autodigestion of retrieved membrane material in the cases of acute hyperparathyroidism similar to characteristics of parathyroid cells stimulated by hypocalcemia in tissue culture.
    Notes: Zusammenfassung Bei 6 Kranken mit akutem Hyperparathyreoidismus werden klinische Befunde, Labordaten und Besonderheiten in der Ultrastruktur der Nebenschilddrüsen den Daten von 47 Kranken mit extrarenalen Hyperparathyreoidismus gegenübergestellt. Typische Unterschiede konnten aufgezeigt werden, die Übergänge sind aber fließend. Beim klinischen Verlauf waren neuromuskuläre Zeichen, psychiatrische und Störungen des Bewußtseins deutlicher in der ersten Gruppe. Beim Vergleich der Labordaten war radioimmunchemisches Parathormon höher in der akuten Gruppe und das Hämoglobin niedriger. Das Gewicht der Adenome und die lichtmikroskopischen Befunde waren nicht unterschiedlich in beiden Gruppen. Die elektronenmikroskopischen Studien des Adenomgewebes zeigten eine erhöhte Hormonausschüttung mit einer deutlichen Beschleunigung der Autodigestion von Membranmaterial. Diese Veränderungen entsprechen etwa denen, wie sie an Nebenschilddrüsengewebe in der Gewebekultur nach Stimulation durch Hypocalciämie gefunden werden.
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  • 27
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    Archives of toxicology 45 (1980), S. 207-211 
    ISSN: 1432-0738
    Keywords: Selenate ; d,l-selenomethionine ; d,l-selenocystine ; Dimethyl selenide ; Trimethylselenonium ion ; Toxicology ; Cataract ; Ontogeny ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The toxic effect of selenium compounds (sodium selenate,d,l-selenomethionine,d,l-selenocystine, dimethyl selenide, and trimethylselenonium ion) was tested in 10-day old male rats. Increasing doses of the compounds were administered an s.c. injection and control animals were not injected. All compounds tested were lethal. Eye lens cataract was induced by the administration of selenate,d,l-selenomethionine, andd,l-selenocystine, while dimethyl selenide and trimethylselenonium ion failed to cause cataract. The cataractogenic effect of the above compounds may be attributed to their interference with glutathione metabolism.
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  • 28
    ISSN: 1432-072X
    Keywords: Claviceps purpurea ; Ultrastructure ; Development ; Sclerotium ; Oleosomes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The development of sclerotia of Claviceps purpurea was investigated by light and electron microscopy. During the first days after infection sterigma and conidiospores are formed. The spores show a moderately developed vacuolar system, they are thick walled and contain about 20% lipid (related to the cell volume) embedded in glycogen. The sterigma are cylindrical unicellular hyphae with electron dense cytoplasm and isolated strongly contrasted lipid droplets. In maturing sclerotia the hyphae become septated with increasingly thick cell walls and a large lipid content. The lipid forms small droplets in young cells, while in the mature sclerotium it occurs in the form of very large drops, occupying the major part of the cell. Simultaneously the composition of the lipid is changed. The mature cells have several nuclei. They are partially connected by osmiophilic substances, forming a network of intercellular spaces.
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  • 29
    ISSN: 1432-072X
    Keywords: Mating tube ; Microtubule ; Tremella ; Ultrastructure ; Yeast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Ultrastructure of the mating tube formed in yeast haplont of the heterobasidiomycete Tremella mesenterica was studied by electron microscopy. Cell wall of the mating tube emerged as evagination of the inner layers, rupturing outer layers of the mother cell wall. Comparison with budding cells suggested that the tube emergence place at bud scar and the process of tube emergence was the same as that of bud emergence. Electron transparent vesicles of 0.1 μm diameter were scattered in the cytoplasm of the mating tube. Nucleus-associated organelle was located at one side of the nuclear envelope which extended towards the mating tube. A few microtubules were detected in the mating tube, but their association with a nucleus was not clear. The cytoplasmic structure of the mating tube was discussed in comparison with that of hyphae of the filamentous fungi.
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  • 30
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    Experimental brain research 39 (1980), S. 121-124 
    ISSN: 1432-1106
    Keywords: Amygdala ; Medial preoptic nucleus ; Median eminence ; Rat ; Synaptic plasticity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Stimulation-dependent changes in synaptic effects were observed in medial preoptic nucleus neurones during stimulation of the amygdala or pyriform cortex in anaesthetized female rats. The changes occurred after 35–240 triple pulse stimuli repeated at 0.89 Hz. Median eminence stimulation did not produce any synaptic change. These data show the existence of synaptic plasticity in the neural pathway from the amygdala and pyriform cortex to the medial preoptic nucleus.
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  • 31
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    Experimental brain research 40 (1980), S. 79-87 
    ISSN: 1432-1106
    Keywords: Spinal tract neuron ; Hypothalamus ; HRP ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The distribution and number of hypothalamospinal tract (HST) neurons were studied following injections of horseradish peroxidase (HRP) at various levels of the rat spinal cord. The hypothalamus was divided into four areas and one nucleus, that is, the dorsal (DHA), posterior (PHA), medial (MHA) and lateral (LHA) hypothalamic areas and the paraventricular nucleus (PVN). The total numbers of HST neurons labeled with HRP varied according to the injection levels: 6,160 (C2 injections), 3,808 (T8), 1,961 (L1), 919 (L7) and 13 (S4). With C2 injections LHA contained 3,464 neurons, which accounted for 56% of the full number of HST neurons; similarly, PVN, 1,114 (18%); MHA, 865 (14%); DHA and PHA, 817 (12%). With L7 injections, LHA contained 444 labeled neurons, which accounted for 48% of the total; PVN, 327 (36%); MHA, 71 (8%); DHA with PHA, 77 (8%). As for the rostrocaudal distribution of labeled neurons, there was only a slight difference between the C2 and L6 injections in LHA, but no difference was noticed in PVN, DHA nor PHA. The present findings suggest that 70% of HST neurons may project to the cervical and thoracic cords. Although the number of labeled HST neurons decreased as the injection sites were placed caudally, no clearcut topographical arrangement was recognized in terms of the spinal projection levels.
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  • 32
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    Experimental brain research 40 (1980), S. 374-382 
    ISSN: 1432-1106
    Keywords: Cinematography ; Electromyography ; Locomotion ; Rat ; Swimming
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Swimming in a mammalian quadruped, the rat, is analyzed in kinematic (joint angles) and electromyographic (EMG) terms. Data were collected on the movements of the hip, knee, ankle, and toe joints and three principle extensors and three flexors of the right hindlimb and compared with similar data collected on the same rats during treadmill stepping. The flexion, or protraction phase of swimming and stepping had many elements in common, including a similarity of EMG activity patterns and corresponding limb movements. However, in the extension, or retraction phase, there were notable differences. Although joint-extensor muscles were all coactive in both conditions, the brevity of the swimming extensor phase precluded the characteristic variation in EMG activity levels seen in the extensors in stepping. The flexors, in particular semitendinosus (ST), exhibited bursts of activity at the end of the extensor phase of swimming which were not present during the comparable period of stepping. The extra burst in ST produced a very rapid knee flexion at this time. Whereas the range of hip joint movement was similar in the two conditions, the ranges of the knee and ankle joints were expanded during swimming. Overall, the evidence suggests that swimming is a very rapid form of a basic locomotor pattern in which the extensors are driven to their maximum contraction rate. The extra extension of the limb derives from the absence of ground reaction forces, allowing the knee and ankle joints to fully extend. The added bursts in the flexors remain to be explained. A discussion of these results in terms of current theories of single limb locomotor pattern generation is presented.
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  • 33
    ISSN: 1432-1106
    Keywords: Rat ; Estrous cycle ; Hypothalamic arcuate nucleus ; Dopamine perikarya ; Cytometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The relative formaldehyde-induced fluorescence intensities and the diameter of cell nuclei of fluorescent perikarya of the arcuate nucleus were recorded in serial cross-sectioned hypothalamic arcuate nuclei of regularly cycling rats (5 estrous and 4 proestrous animals). Stress-induced changes of cytometric parameters were avoided by preadaptation of animals to handling procedures. Dopamine neurons in a 75 μm thick periventricular layer of the arcuate nucleus exhibited significantly smaller nerve cell nuclei and significantly reduced relative fluorescence intensities in proestrous rats. Both of these cytometric parameters indicate a decrease in the activity of periventricular dopamine neurons of the arcuate nucleus. The reported findings might support the hypothesis that dopamine inhibits the release of LH-RH.
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  • 34
    ISSN: 1432-1106
    Keywords: Ventromedial thalamic nucleus ; Cerebellar degenerating boutons ; Ultrastructure ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Terminal degeneration of cerebellar afferents in the ventral medial thalamic nucleus (VM) was studied in cats at the ultrastructural level after uni- or bilateral lesions in the brachium conjunctivum (BC). To achieve discrete lesions within the BC, a new very accurate stereotaxic technique was used. Numerous large terminals belonging to a population of so-called LR boutons were observed degenerating in the VM. The boutons displayed a wide variety of degenerative changes. Some revealed the features of the classical neurofilamentous type of degeneration. Others, although containing a slightly increased number of neurofilaments, featured much more prominently large numbers of coated vesicle shells and heavy accumulations of a flocculent electrondense material. Degeneration in a third group of boutons similar to some extent to the light type of degeneration was characterized by tight clumping of enormously swollen or distorted synaptic vesicles within a light matrix. At later stages, however, all these boutons were believed to become shrunken and electron-dense since intermediate stages between the light- and dark-appearing boutons were observed. The degenerating cerebellar boutons formed asymmetrical synaptic contacts. Groups of 3 or 4 boutons terminated upon dendrites of projection neurons synapsing more frequently on spines than on dendritic stems. The synaptic contacts between cerebellar boutons and the vesicle-containing dendrites of local circuit neurons were encountered as often if not more than the contacts on projection neuron dendrites. Triads consisting of cerebellar boutons and dendrites of both types of neurons were observed very regularly. This synaptic arrangement provides the anatomical basis for the modification of cerebellar input in the VM by interneurons.
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  • 35
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    Experimental brain research 38 (1980), S. 11-17 
    ISSN: 1432-1106
    Keywords: Cerebellum ; Pontine nuclei ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Microinjections of horseradish peroxidase (HRP) were made in different sublobules of the uvula (lobule IX, a, b, and c of Larsell, 1952) of the cerebellar cortex in the rat. These injections resulted in retrograde labeling of cells located in the pontine nuclei. Sublobule IXa receives a predominant input from a single column of cells situated in a dorsointermediate position in the caudal pontine nuclei. Sublobules IXb and IXc receive a pontine projection from two different columns of cells, one medial and one lateral. The location of the labeled cells in the lateral part of the caudal pons suggests a topographic projection to the subdivisions of the uvula. Sublobule IXa receives a projection from a distinct dorsointermediate region and sublobule IXb and IXc receive a projection from partially overlapping ventral regions. The cells of origin in the medial pons are organized such that more dorsally located cells project to sublobule IXc and ventrally located cells project to sublobule IXb with extensive overlap. These differential patterns of projections to the sublobules of the uvula along with other data in the literature suggest that sublobule IXa may be involved with different functional correlates than sublobules IXb and IXc.
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  • 36
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    Experimental brain research 39 (1980), S. 241-248 
    ISSN: 1432-1106
    Keywords: Olfactory peduncle neurons ; Axonal branching ; Supernormal period ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Electrophysiological methods were employed to study the axonal properties of the neurons of anterior olfactory nucleus (AON), transition zone (TZ), and rostral prepyriform cortex (RPPC) and their projections towards the ipsilateral and contralateral olfactory bulb (IOB, COB) in the rat. Of 91 antidromically driven cells, 39 (43%) and 32 (35%) responded to IOB and COB stimulation, respectively; 20 (22%) were discharged from both bulbs. Collision tests performed on the latter group indicated that these neurons have a short main axon which divides near the soma, projecting one branch to the COB and a thinner one toward the IOB. Mean conduction velocities of axons projecting to the IOB and the COB were 0.4 m/s and 0.7 m/s, respectively, the faster conducting axons having shorter refractory periods. Of the 38 neurons tested, 92% showed decreases in threshold and latency (up to 20% of control antidromic latency) after a test volley that was preceded by a conditioning pulse at intervals of 20–215 ms. Latency decreases were greater for slowly conducting axons than for the faster ones. These after-effects of impulse activity in OB afferent axons were attributed to the presence of a supernormal period of increased conduction velocity and excitability similar to that found in the olfactory nerve (Bliss and Rosenberg, 1974).
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  • 37
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    Experimental brain research 40 (1980), S. 164-169 
    ISSN: 1432-1106
    Keywords: Rat ; Avoidance conditioning ; Parafascicular nucleus ; Dopamine ; Noradrenaline
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Male rats were subject to bilateral lesions in the parafascicular nucleus (PF) of the thalamus. The lesions had little or no effect on the performance of a pre-operatively acquired conditioned avoidance response. However, the PF lesioned animals displayed an enhanced response to the dopamine receptor blocking agents haloperidol or pimozide but not to the noradrenaline receptor blocking agent phenoxybenzamine. The results indicate that intralaminar thalamic nuclei and dopaminergic extrapyramidal motor pathways are functionally connected.
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  • 38
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    Calcified tissue international 32 (1980), S. 63-68 
    ISSN: 1432-0827
    Keywords: Rat ; Bone formation ; Fluorochrome ; Microphotometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary A method for quantitative studies of the formation rate of bone has been developed. After vital staining with calcein, the fluorescence of a bone section was measured with a microphotometer controlled by a mini computer. After staining the bone structure with alizarin red S in a second step, the section was measured in transmitted light. The two data sets were combined and the shortest distances between the bone surface and the fluorescence lines were computed. With this information the distance distribution and the bone area between the label and the surface could be calculated in two different ways: with the single labeling and the continuous labeling techniques. The advantages and disadvantages of the two methods are discussed and compared with those of other techniques.
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  • 39
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    Calcified tissue international 32 (1980), S. 113-122 
    ISSN: 1432-0827
    Keywords: Rat ; Bone ; Metaphysis ; Quantitative ; Aging
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The purpose of this work was to analyze the proximal tibial metaphysis of the 170 g rat in a quantitative histologic fashion which would allow some relation to tissue age to be established. Stained 3 µm thick tissue sections were analyzed with the aid of a Merz grid on an eyepiece reticule and a light microscope. Tissue mass and cell distribution were studied in all areas. The rate of change in tissue mass during aging of the metaphysis was calculated. Two regions of the metaphysis were identified. One, corresponding to the primary spongiosa, less than 4.45 days of age, is a region of high turnover of hard tissue and high numbers of osteoblasts and osteoprogenitor cells. The other, corresponding to the secondary spongiosa, is a region of relatively low net tissue turnover and low numbers of osteoblasts and osteoprogenitor cells. Osteoclasts were found relatively more uniformly distributed through the metaphysis than were osteoblasts and osteoprogenitor cells. The rate of bone formation in the primary spongiosa is 50 times that found in the Haversian bone of the rib of 5-year-old humans and about 500 times that found at the cortical-endosteal surface of ribs of 5-year-old humans. It is argued that both cell distribution and tissue distribution in the metaphysis support the concept that osteoblasts and osteoclasts, rather than osteocytes, are responsible for the maturation of the metaphysis. The inhomogeneous distribution of both cells and tissue in the metaphysis has definite meaning for the interpretation of findings concerning the incorporation of radionuclides into the skeleton.
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  • 40
    ISSN: 1432-0827
    Keywords: Rat ; Hypophysectomy ; Dietary phosphorus deprivation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The demands of growth are known to exacerbate the effect of phosphorus deprivation (PD). We examined whether changes associated with PD could be prevented in young rats in which growth and growth hormone (GH) were eliminated by hypophysectomy (HPX) and whether PD in normal intact rats (INT) was associated with increased secretion of GH. INT or thyroxine- and ACTH-replaced HPX rats were fed one of the three diets: 0.31% P (NP); 0.027% P (LP), and 0.31% P, pair-fed with LP-mates (NP-PF). The results indicate that HPX did not qualitatively alter several physiologic responses to PD: (a) serum and urinary phosphorus (P) decreased and urinary calcium (Ca) increased; (b) net intestinal Ca retention fell and duodenal sac uptake of45Ca rose; and (c) external P balance was restored and duodenal sac uptake of32P-phosphate increased. Only the hypercalcemia seen in INT, LP rats was prevented by HPX. In INT rats serum immunoassayable GH levels, measured in single samples, were not different between different dietary groups while pituitary bioassayable GH was reduced in both LP and NP-PF rats when compared to the NP rats. Thus, except for hypercalcemia, the physiologic responses associated with PD are not prevented by the elimination of growth and GH, and the development of these responses in INT rats was not associated with a consistent or specific alteration in GH secretion.
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  • 41
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    European journal of pediatrics 134 (1980), S. 69-74 
    ISSN: 1432-1076
    Keywords: Achondrogenesis type I ; Ultrastructure ; Chondrocytes ; Cytoplasmic inclusions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The light- and electron-microscopic structure of articular and costal cartilage in a case of achondrogenesis type I has been described. The most characteristic ultrastructural change in the chondrocytes was conspicuous dilatation of the rough endoplasmatic reticulum (RER) which contained amorphous electronopaque material. This change in the RER was accompanied by marked hypertrophy of the Golgi apparatus; the matrix was basically unchanged.
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  • 42
    ISSN: 1432-0827
    Keywords: Rat ; Calvarium ; Electron microscopy ; Preosteoclasts ; Osteoclasts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary This is a study of the fine structure of cells of the 20-day fetal rat calvarium. Special attention is given to identifying and characterizing preosteoclasts. These cells are relatively common and located largely, but not exclusively, at the endocranial bone surface. The preosteoclasts are characterized by abundant mitochondria, an incomplete perinuclear Golgi apparatus, and variable-shaped dense granules. The dense granules are unique in appearance in that they contain an internal dense matrix surrounded by a clear halo. Most granules are circular in shape but some are elongate or tubular in form. Granules with identical appearance are observed in osteoclasts. The preosteoclasts are mononucleate, or occasionally binucleate. It is suggested that because preosteoclasts are morphologically distinctive and relatively abundant, it should be feasible to separate these cells from a heterogeneous cell isolate.
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  • 43
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    Virchows Archiv 389 (1980), S. 103-117 
    ISSN: 1432-2307
    Keywords: Gonadal dysgenesis ; H-Y antigen ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The gonads of 4 phenotypically female individuals with XY chromosomal constitution and signs of virilisation were examined by light microscopy. Electron microscopic examination was also performed in two cases. Serological analysis of H-Y antigen titer yielded positive results. The matrix of the gonads is shown to be ovarian stroma, in which tubular and follicular structures are embedded. The epithelia of the follicles resemble granulosa cells of the ovary, the tubular epithelia are resemble Sertoli cells. Tubules and follicles both show extensive regressive changes. A varying number of Leyding cells/stroma lutein cells were found in each gonad. The different degree of development of testicular and ovarian structures in the dysgenetic gonads might be explained by a defect of the gonadal specific receptor for the H-Y antigen, this defect varying in time of occurrence, duration and severity.
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  • 44
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    Virchows Archiv 389 (1980), S. 287-305 
    ISSN: 1432-2307
    Keywords: Myeloproliferative disease ; Osteomyelofibrosis ; Bone marrow biopsy ; Blast crisis ; Ultrastructure ; Basophilic leukaemia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The clinical and morphological findings are presented in two patients suffering from myelofibrosis and osteomyelosclerosis which terminated in an acute blastic crisis. Clinical follow-up data and light microscopy of the bone marrow however, revealed a chronic megakaryocytic-granulocytic myelosis (CMGM) with progression into myelofibrosis during the course of disease. In one patient the blastic transformation involved predominantly basophils, and in the other, neutrophils, with an accompanying abnormal proliferation of megakaryocytes in both cases. Electron microscopy of this cell population demonstrated remarkable atypicalities of the neutrophilic, basophilic and megakaryocytic cell lines. These abnormalities consisted of a nuclear-cytoplasmic asynchrony and a partial arrest of maturation, sometimes resulting in bizarre cell forms. Our investigations support the hypothesis of a mixed cellularity type of myelosis with a gradual and insiduous progression into osteomyelofibrosis/-sclerosis and a potential blastic crisis. In the evolution of blastic crisis all cell lines may be transformed, but with predominance of one population — basophils and neutrophils in our two cases — in addition to atypicalities of megakaryocytes.
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  • 45
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    Virchows Archiv 389 (1980), S. 307-324 
    ISSN: 1432-2307
    Keywords: Polycythemia vera ; Secondary polycythemia ; Histopathology ; Ultrastructure ; Cytogenetics ; Bone marrow biopsy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Clinical and morphological studies including light microscopy, electron microscopy and karyotyping of the bone marrow, were performed on a total of 164 patients with polycythemic conditions. A final diagnosis was obtained from clinical findings and histopathology of plastic embedded core biopsies of the bone marrow including sequential examinations. 51 patients revealed a secondary polycythemia whereas 113 displayed polycythemia vera (P. vera). In this last group 83 cases have persisting P. vera. 30 showed a transgression towards chronic myeloid leukemia with or without accompanying myelofibrosis — osteomyelosclerosis (so called chronic megakaryocytic-granulocytic myelosis — CMGM). The histopathology of the bone marrow in P. vera revealed consistent alterations which are useful in distinguishing this disorder from secondary polycythemia (SP) and CMGM: depletion of iron storage, increased neutrophilic granulopoiesis but no gross atypia in maturation, polymorphism of megakaryocytes with conspicuous giant forms and dilatation and increased branchings of venous sinusoids. Electron microscopic findings were in agreement and showed further abnormalities of cytological maturation in the erythrocytic and granulocytic lineage. Cytogenetic studies in 27 non-treated patients with P. vera revealed the Philadelphia chromosomes in 2 cases, whereas in SP only minor chromosomal anomalies have been encountered in a few patients. It is concluded that histopathology of trephine biopsies of the bone marrow is an invaluable aid to establish a correct diagnosis, differentiating P. vera from the other potentially polycythemic disorders and helping to detect a possible progression towards leukemia at an early stage. Cytogenetic investigations may show early structural and numerical abnormalities of the karyotype and possibly precede a presumptive transgression towards myeloid leukemia (CMGM). A simultaneously performed histological and chromosomal examination of bone marrow samples is therefore desirable in each case of a polycythemic condition.
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    Virchows Archiv 389 (1980), S. 325-341 
    ISSN: 1432-2307
    Keywords: Polycythemia vera ; Myeloid leukemia ; Histopathology ; Ultrastructure ; Cytogenetics ; Survival
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Of 113 Patients with polycythemia vera (P. vera) who had been followed for the last 8 years, 30 cases (27%) developed myeloid leukemia with fibrosis of the bone marrow. Core biopsies of the bone marrow including sequential examinations in several cases revealed neoplastic proliferation of neutrophil granulopoiesis and an atypical megakaryopoiesis with accompanying fibrosis of varying degrees. These alterations were consistent with a subtype of chronic myeloid leukemia — the so called chronic megakaryocytic-granulocytic myelosis (CMGM) — and correspond to (agnogenic) myeloid metaplasia with osteomyelofibrosis/-sclerosis. 5 of those 30 patients showed spontaneous transgression into myeloid leukemia, none of them had received any ionizing radiation or cytostatic therapy. A blast crisis or so called acute leukemia in P. vera was seen only in one patient who was treated by an overdose of radioactive phosphorus and later evolved into osteomyelosclerosis with blastic transformation. These findings of a chronic leukemia or CMGM arising from P. vera was further confirmed by atypia of ultrastructure and particularly by our cytogenetic evaluation. Chromosomal studies showed a Ph′-chromosome to be present in 5 of 8 patients with CMGM and myelofibrosis. Clinical and statistical evaluation of survival times showed a median survival expectation of all P. vera patients of 15 years. Life expectancy of the patients who still displayed P. vera was more favorable than those cases with transformation into CMGM, disregarding any therapy. Transformation of P. vera into CMGM occurred about 8 years after the onset of disease and following transgression into leukemia, half of these patients were dead after 2.5 years. Our results demonstrate that P. vera represents a “panmyelosis” with an inherent malignant nature, or a neoplastic proliferation of all three cell lines. This concept is supported by several facts: atypia of cytological differentiation as observed by light- and electron microscopy of the bone marrow, chromosomal anomalies with aneuploidy and an infrequent Ph'-marker, spontaneous transgression into chronic myeloid leukemia or its subtype CMGM without relevant therapy and a clonal evolution as shown by enzymatic studies reported in the literature.
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  • 47
    ISSN: 1432-2307
    Keywords: Parathyroid carcinoma ; Tumour progession ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A case of parathyroid carcinoma in a 74-year-old female patient was studied by light and electron microscopy. The malignancy of the parathyroid tumour was confirmed by local recurrence and infiltration of adjacent structures. The tumour was composed of uniform chief cells without mitoses. Ultrastructurally, the cells were characterized by tortuous plasma membranes, numerous secretion granules, an extensive rough endoplasmic reticulum and lack of lipid vacuoles, all indicating hyperactivity, but not malignancy. At death, the autopsy revealed local recurrence of tumour tissue, but no distant metastases. Both light and electron microscopy showed that considerable dedifferentiation of the tumour tissue had occurred. The tumour cells were now characterized by a marked nuclear pleomorphism and a coarse clumping of the chromatin. The presence of secretion granules alone suggested a parathyroid origin. Thus, at death there was unequivocal histological evidence of a carcinoma, whereas no such diagnosis could be made from the early biopsy. The clinical course alone indicated the malignant nature of the lesion.
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  • 48
    ISSN: 1432-2307
    Keywords: Pituitary adenoma ; Prolactin ; Ultrastructure ; Immunohistochemistry ; Morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Fifteen cases of pituitary adenoma, 14 of which were associated with hyperprolactinemia, were studied by observation and granule morphometry of electron micrographs, immunohistochemistry and sequential observation of in vitro release with regard to hormone production, storage and secretion. Adenoma cells of 6 cases with marked elevation of plasma prolactin were sparsely granulated, showed characteristic ultrastrucures including the presence of small secretory granules, well developed Golgi and rough membranes, misplaced exocytosis, and positive or negative immunostaining for prolactin. These adenomas also showed vigorous release of the hormone into the circulation and/or culture medium. In vitro studies showed that negative immunostaining of adenoma cells did not preclude the production and secretion of the hormone. One densely granulated adenoma containing cells with numerous lactotroph type granules showed moderate release of prolactin into the circulation. In an acromegalic case associated with both high plasma growth hormone and prolactin, some cells were shown by immunohistochemistry to store both hormones. There were 4 adenomas which could not be shown to produce, store and secrete prolactin by any method available.
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  • 49
    ISSN: 1432-2307
    Keywords: Eosinophilic granuloma ; Frontal lobe ; Histiocytosis-X ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The clinical symptoms, pathological findings and surgical treatment of a case of primary frontal lobe eosinophilic granuloma are presented. Initially a frontal mass was detected that clinically seemed like a low-growth tumor. After operation, the histological, cytochemical and ultrastructural studies showed positive acid phosphatase, α-naftil-esterase, oil-red and PAS reactions of tumoral cells and the presence of rod-shaped bodies in proliferative histiocytes, all which confirmed the pathological diagnosis of eosinophilic granuloma. Other osseous or visceral histiocytosis-X signs were not observed. The patient remains asymptomatic after a postoperative follow-up of 2 years.
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  • 50
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    Virchows Archiv 389 (1980), S. 1-11 
    ISSN: 1432-2307
    Keywords: Soft tissue sarcoma ; Myofibroblasts ; Ultrastructure ; Host response
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A series of 129 soft tissue sarcomas was examined ultrastructurally to determine in which neoplasms and to what extent myofibroblasts could be demonstrated. Twenty cases of fibromatosis and fasciitis served as controls. Myofibroblasts were identified in all 30 cases of malignant fibrous histiocytoma and all 4 cases of well-differentiated sclerosing liposarcoma. Though most numerous in areas of desmoplasia, in no instance did myofibroblasts constitute the dominant cellular constituent of either neoplasm. Myofibroblasts were identified with lesser frequency and in smaller numbers in fibrosarcoma, synovial sarcoma, malignant hemangiopericytoma and neuroblastoma. None were observed in a wide assortment of diverse sarcomas in which desmoplasia was not a feature. In comparison each lesion judged by light microscopy to represent either fibromatosis or fasciitis was composed principally of myofibroblasts. The demonstration of abundant myofibroblasts within a soft tissue lesion which has been subjected to wide sampling strongly suggests a benign proliferative process as opposed to a malignant neoplasm. It is hypothesized that myofibroblasts observed within collagenized regions of soft tissue sarcomas may constitute an expression of host response to neoplasia.
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  • 51
    ISSN: 1432-2307
    Keywords: Cortisol ; Myocardium ; Ultrastructure ; Morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Male Wistar rats were treated with high cortisol doses for 1 week. The dose administered daily was 15 mg per animal in group 1 (7 animals) and 30 mg in group 2 (7 animals). 7 rats served as control group. After cortisol treatment the body weights decreased due to skeletal muscle catabolism and the heart weights increased. Morphometric analysis of the left ventricular posterior papillary muscles gave evidence that the increased heart weights resulted from an increased number of mitochondria and an increased volume of the cytoplasm, whereas the myofibrillar mass was not affected. The surface area of inner mitochondrial membranes (+cristae mitochondriales) per myofibrillar unit volume increased from 15.7 μ2/μ3 to 21.3 μ2/μ3 in group 1 and 21.4 μ2/μ3 in group 2. Ultrastructural changes indicating myocardial cell damage were absent. Similar quantitative results have been reported to occur in the early phase of cardiac overload. For elucidating the hemodynamic effects of glucocorticoid a second experiment was performed: 7 Wistar rats were treated with cortisol in the same way as group 1, 7 others of the same body weight served as control. The systolic arterial pressure was significantly elevated in the cortisol group. Though myocardial tissue is known to be able to accumulate large quantities of glucocorticoids our results indicate that the application of high cortisol doses for a short time does not produce myocardial cell damage and does not suppress the myocardial adaption to the glucocorticoid-induced hypertension, i.e. hypertrophy. On the contrary, it seems to be possible that the adaption process is itself facilitated or accelerated by the presence of high cortisol concentrations in the heart. This thesis is supported by the considerably higher relative heart weights in the cortisol groups and is in agreement with observations reported by other authors.
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  • 52
    ISSN: 1432-2307
    Keywords: Tumor promotion ; Tumor initiation ; DMBA ; TPA ; Two-stage carcinogenesis experiment ; Carcinogenesis ; Cocarcinogenesis ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In contrast to a previous report by Shubik, the validity of the 2-stage skin carcinogenesis experiment was demonstrated in the rat. The modified experiment was carried out in female Sprague-Dawley rats using intragastrically administered DMBA as a carcinogen and the topically applied phorbol ester TPA as a promoter. Seven groups of animals were used. Two groups were treated with TPA only, two groups were initiated only with DMBA, two further groups were both initiated and promoted, and one group served as a control. Each of the initiated/promoted groups or only initiated or promoted groups contained one sub-group in which the animals had been bilaterally ovarectomized prior to the experiment. Hyperplasia of the dorsal epidermis occurred only in the promoted and in the initiated/promoted groups. Tumors of the back skin were observed exclusively after initiation/promotion. Ovarectomy — leading to a prolonged survival time of the animals — seems to be crucial for the manifestation of malignant skin tumors. Initiation/promotion also gives rise to tumors of the forestomach, the small intestine, the liver and the colon. Tumors in other organs (especially in the mammary gland and the Zymbal gland) were also be observed after initiation alone.
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  • 53
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    Virchows Archiv 386 (1980), S. 331-341 
    ISSN: 1432-2307
    Keywords: Fluorocarbon ; Extracorporeal circulation (EEC) ; Pulmonary ; systemic embolism ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary After intravenous injection of 0.1 ml Fluorocarbon (FC) into the caudal vein of rats clear droplets which are reminiscent of gas emboli appear in the pulmonary and cerebral arteries. These droplets cannot be stained with Azan, haematoxylin-eosin, Nile blue sulfate, Sudan black B, and Sudan III in Paraplast embedded or frozen sections. Gas chromatography of affected lung tissue reveals a high concentration of FC. The clear droplets are the histological correlates of FC emboli which lead to haemorrhagic lung infarction and ischaemic brain infarcts. After intralienal injection FC induces haemorrhagic infarcts of the spleen near the injection site and massive embolization of the intrahepatic portal veins with consequent liver cell necrosis. FC droplets are phagocytosed by hepatic sinusoidal lining cells. Due to the absence of a specific method for identifying FC embolization of renal vessies is difficult to assess.
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  • 54
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    Virchows Archiv 387 (1980), S. 279-288 
    ISSN: 1432-2307
    Keywords: Pituitary ; Ultrastructure ; Hypophysectomy ; Regeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Male Wistar rats were partially hypophysectomized and sacrificed at intervals of from 2 days to 1 year following the operation. The resected material was examined under the light microscope and the residual pituitary under the light and electron microscope. Neither regeneration nor an anatomical restoration of the adenohypophysis occurred even one year after partial hypophysectomy. An increased number of small chromophobe stem cells and juvenile chromophil cells were found in the residual pituitary. The amount of mitoses were not significantly increased. The ACTH, FSH and prolactin producing cells demonstrated electron microscopically distinct changes which were interpreted as signs of intensified activity. This can be seen as a “functional regeneration” to maintain vital pituitary function for the organism.
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  • 55
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    Virchows Archiv 387 (1980), S. 353-369 
    ISSN: 1432-2307
    Keywords: Granulosa cell tumors ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructural features of three granulosa cell tumors are presented. The neoplastic non-luteinized granulosa cells are characterized at sub-microscopical level by severely indented nuclei with prominent nucleoli, sparse to moderately developed predominantly granular endoplasmic reticulum, scanty lipids and lysosomes, small mitochondria with lamellar cristae and abundant intracytoplasmic filamentous material. The luteinized cells display a strongly developed tubular agranular endoplasmic reticulum and mitochondria with tubular cristae. These findings are compared with those of previous reports and discussed in relation to the well-known hormonal activity of these tumors.
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  • 56
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    Virchows Archiv 385 (1980), S. 283-291 
    ISSN: 1432-2307
    Keywords: Hodgkin's disease ; Myofibroblasts ; Ultrastructure ; Nodular sclerosis ; Host response
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Ten cases of nodular sclerosing Hodgkin's disease involving lymph nodes were studied by electron microscopy to determine the ultrastructural composition of the nodule-stromal interphase and the collagenized regions. In addition to a few lymphocytes, rare eosinophils and neutrophils, abundant filamentous and granular electron dense material, collagen fibers and myofibroblasts were observed in all instances. Since myofibroblasts possess contractile and synthetic properties, it is likely they contribute to the retraction and sclerosis which together represent one of the morphologic hallmarks of the disease. The dense fibrosis and contractile state of such tissue may constitute a beneficial host response to contain and limit local and vascular invasion by the neoplastic cellular population, thus contributing to the relative benignity of this form of Hodgkin's disease.
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  • 57
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    European archives of oto-rhino-laryngology and head & neck 226 (1980), S. 123-128 
    ISSN: 1434-4726
    Keywords: Organ of Corti ; Organ-specific polypeptides ; Two-dimensional polyacrylamide gel electrophoresis ; Guinea pig ; Rat ; Actin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Two polypeptides, OCP-I and OCP-II, specific to the organ of Corti of the guinea pig and the rat, were detected by two-dimensional polyacrylamide gel electrophoresis. They were neither present in other inner ear structures, nor in other organs tested. The two polypeptides constitute a substantial portion of the total protein of the organ of Corti. Both inner and outer layer of the organ of Corti contained approximately equal amounts of OCP-I and OCP-II. The molecular weights of OCP-I and OCP-II are 37,000 and 22,500 daltons, respectively. The corresponding pI values are 4.9 and 5.1, respectively. In addition, actin and tubulin were detected in both layers of the organ of Corti.
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  • 58
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    European archives of oto-rhino-laryngology and head & neck 229 (1980), S. 45-53 
    ISSN: 1434-4726
    Keywords: Vitamin A-Mangel bei jungen Ratten ; Ultrastruktur ; Akustische Sinnenzellen ; Ganglion spirale cochleae ; Vitamin A deficiency in young rats ; Ultrastructure ; Acoustic sensory receptor ; Ganglion cell
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Microscope studies of the inner ear in rats with chronic vitamin A deficiency have rendered contradicting results. In our electron microscope study of the sensory cells of the inner ear in young rats with vitamin A deficiency we found that the cuticle is missing in outer hair cells. In the inner hair cells the cuticle is subtotally lacking. Furthermore, we found changes in the reticular system of the intermediate zone and massive degenerative changes in the afferent nerve system including the ganglion cells of the ganglion spirale cochleae. These morphological changes together with the recent findings of high concentrations of vitamin A in Corti's organ support the hypothesis that the acoustic sensory receptors contain of functionally depend upon vitamin A.
    Notes: Zusammenfassung Histologische Untersuchungen über die Auswirkung eines chronischen Vitamin A-Mangels auf die Strukturen des Innenohres hatten widersprüchliche Ergebnisse gebracht. Nach einem sechswöchigen Vitamin A-Mangel bei jungen Ratten fanden wir in äußeren Haarzellen ein Fehlen der elektronendichten, homogenen Cuticula. In den inneren Haarzellen kam es ebenfalls zu einer deutlichen Auflösung der Cuticula. Weiter fanden wir eine Fragmentierung und Verminderung des reticulären Systems der Intermediärzone. Deutliche Degenerationszeichen fanden sich bei den afferenten Nervenendigungen und in den Ganglienzellen des Ganglion spirale cochleae. Die Ergebnisse weisen auf eine spezielle Bedeutung des Vitamin A für die Funktionsfähigkeit der Sinneszellen hin.
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  • 59
    ISSN: 1432-0738
    Keywords: Pesticides ; DNA repair ; Human lymphocytes ; Man ; Rat thymocytes ; Rat ; DNA synthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The action of seventeen pesticides (insecticides, fungicides and herbicides) has been studied with short-term in vitro system using rat thymocytes and/or human lymphocytes. The parameters studied were: a) the action of chemicals tested in scalar doses on DNA synthesis of rat thymocytes; b) damage exerted by pesticides on human lymphocyte DNA measured as unscheduled DNA synthesis; c) the interference of chemicals tested with human lymphocyte repair capability after damage exerted on cells by ultraviolet rays. The results obtained suggest that some of tested pesticides don't induce damages to human lymphocyte DNA, some others elicit low DNA repair if compared to the repair following a standard ultraviolet irradiation and some of them (6/17) exert a marked inhibition of cell repair processes after ultraviolet irradiation. Data are discussed on the basis of a possible role played by these substances as carcinogenic agents in the environment.
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  • 60
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    Archives of toxicology 43 (1980), S. 155-161 
    ISSN: 1432-0738
    Keywords: 1α,25-dihydroxycholecalciferol ; Calcification ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The oral administration for 5 days of excess 1α,25-dihydroxychole-calciferol [1,25(OH)2D3] at doses of 1, 5, and 25 μg/kg to rats, beginning at the age of 2 or 10 days, produced dose-dependent reductions in weight development and additional calcification near the skeleton. Alizarin red S stained skeleton revealed calcific deposits near the bones of the head, near the neural arches, between the ribs, along the bones both of the fore limbs and, to a lesser extent, of the hind limbs. Historically, the deposits appeared to be localized primarily in the subepithelial connective tissues. Starting treatment with 1,25(OH)2D3 (25 μg/kg for 5 days) at the age of 20 days produced additional calcification in 1 of 8 rats at only 1 location (lower jaw). Additional calcification as described above could no longer be induced by 1,25(OH)2D3 in 30-day-old rats using doses up to 25 μg/kg and 10 daily treatments. We conclude that the sensitivity of young rats to 1,25(OH)2D3-induced additional calcification, which differs in localization from that observed in adult rats, decreases with the maturation of the animals.
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  • 61
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    Archives of toxicology 43 (1980), S. 257-262 
    ISSN: 1432-0738
    Keywords: Bromobenzene ; Cytochrome P-450 ; Cytochrome reductase ; Glucuronyltransferase ; Lipoperoxidation ; Liver ; Mixed-function oxidase ; Peroxide ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In acute oral studies, the effect of bromobenzene on hepatic microsomal enzymes was investigated. Neither glucuronyltransferases nor cytochrome c reductase showed significant changes. Most of the mixed-function oxidases studied were inhibited with the exception of ketamine-N-demethylase. The data indicate that bromobenzene or its epoxide acts on cytochrome P-450 but not on all cytochrome P-450 species, and does not affect the reductase and the glucuronyltransferases. Microsomal lipoperoxidation and microsomal H2O2 formation were increased.
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  • 62
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    Journal of cancer research and clinical oncology 96 (1980), S. 281-285 
    ISSN: 1432-1335
    Keywords: Carcinogenesis ; Thyroid gland ; Rat ; NMU ; MTU
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Seventy-five female Wistar rats of 150 g each were given 3×40 mg/kg body weight nitrosomethylurea (NMU) and 4 weeks later until death (in the 9th–60th week) methylthiouracil (MTU), as a 0.1% solution in their drinking water. After 2 months, in the almost colloid-less thyroid gland individual foci appeared which consisted of sometimes colloid containing follicles with increased cytoplasmic and nuclear basophilia; they increased in number during the subsequent weeks and finally resulted in nodes with different morphologic structures. From the 16th week on there were tumors infiltrating the capsule, and after the 24th week there were angioinvasive carcinomas. Thirteen rats had developed lung metastasization after the 30th week. Cytology could only distinguish between the follicular carcinomas of low differentiation and the follicular adenomas. If these findings are applied to human pathology, one would have to reckon with adenomas which can develop their malignant characteristics without necessarily changing their histologic and cytologic appearance.
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  • 63
    ISSN: 1432-1335
    Keywords: Gastric carcinoma ; Intestinal metaplasia ; N-Propyl-N′-nitro-N-nitrosoguanidine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Sequential studies were made on the histopathologic changes in the glandular stomach of rats induced by a weak carcinogen, N-propyl-N′-nitro-N-nitrosoguanidine (PNNG). Fiftyfour rats were given 100 μg/ml of PNNG in their drinking water for 44 weeks, and then normal tap water until the end of the experiment. Rats were killed at intervals between week 1 and week 88. No marked atrophy or ulceration of the mucosa was found between week 1 and the end of the experiment. Focal intestinal metaplasia was found in week 19 and its incidence increased during the experiment. Adenocarcinoma in situ with extreme cellular atypia was found in mucosa with a normal appearance in week 67. An adenocarcinoma invading the submucosa was found in week 69, and one invading the serosa in week 88. All these pathological lesions were found on the anal side of the pyloric region. No pathologic changes were found in the fundic region. The sequential changes of the mucosa of the glandular stomach induced by this weak gastric carcinogen, PNNG, were very different from those induced by the potent gastric carcinogen, N-methyl-N′-nitro-N-nitrosoguanidine (MNNG). Gastric carcinoma induced by PNNG seems to be more similar to human gastric cancer than that induced by MNNG.
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  • 64
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    Archives of gynecology and obstetrics 230 (1980), S. 49-75 
    ISSN: 1432-0711
    Keywords: Ovarian Sertoli-Leydig cell tumors ; Ultrastructure ; Histogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Ovarian Sertoli-Leydig cell tumors are rare, most of them being endocrinologically active and causing virilization. Their histogenesis and nomenclature are still under discussion. Six such tumors were identified in the Laboratory for Histopathology of the University Women's Hospital, Zürich. The clinical data as well as the macroscopic, microscopic and ultrastructural features of these tumors are analysed and discussed. In an attempt to clarify their histogenesis, the ultrastructural features of these tumors have been compared with those of two granulosa cell tumors as well as with those of a testis in a patient with testicular feminization. Our own results and a study of published data suggest that Sertoli-Leydig cell tumors arise from ovarian stroma. Because of their obvious morphological similarities to testicular structures they should be termed “gonadal stromal tumors of android type”.
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  • 65
    ISSN: 1432-0738
    Keywords: Ultrastructure ; Morphometry ; Ageing ; Pentachlorophenol ; Liver
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Altersabhängige Unterschiede im Reaktionsverhalten der Leber bei männlichen Wistarratten nach intraperitonealer Applikation von 30 mg technischem Pentachlorphenol (PCP) pro Kilogramm Körpergewicht über 15 Tage wurden feinstrukturell-morphometrisch ausgewertet. Neben einer altersabhängigen Erhöhung des relativen Lebergewichts und einer Abnahme des Körpergewichts konnten umfangreiche Alterationen an den Hepatocytenzellkernen und Zellorganellen festgestellt werden. Die Ergebnisse belegen, da β PCP neben Veränderungen an den Mitochondrien und Microbodies eine Proliferation der Membranen des glatten ER und eine Verminderung von Membranen des rauhen ER hervorruft.
    Notes: Abstract Age-dependent effects of technical pentachlorophenol (PCP) on male rat livers were investigated after a 15 day treatment with PCP, 30 mg/kg/d body weight. The liver tissues were investigated morphometrically at light and electron microscopical levels. Statistically significant alterations of nuclei and organelles of the hepatocytes were described.
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  • 66
    ISSN: 1432-0738
    Keywords: Methylmercury ; Inorganic mercury ; Rat ; Subcellular distribution ; Biotransformation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Accumulation of inorganic mercury in subcellular fractions of the kidney, liver, and brain of rats was studied during 48 days after a single injection of 25 mg/kg of methylmercury chloride. The highest ratio of inorganic to total mercury was seen in the cytosol of kidney, 80% of the total being as inorganic mercury at day 48. The ratio in the mitochondria and microsomes of kidney attained a maximum level (about 50% of the total as inorganic) at day 26–37. In the liver, the ratio was strikingly low in the cytosol and microsomes as compared to the light and heavy mitochondria where about 40% of the total was present as inorganic maximally at day 26. The ratio in the brain, determined up to day 15, was very low as compared with the kidney and liver, showing less than 3% of the total in the mitochondria, microsomes, and cytosol, and 5.4% in the myelin fraction. The high accumulation of inorganic mercury in the cytosol of kidney was closely related to metallothionein-like component, while those in the mitochondria and microsomes of kidney and in the mitochondria of liver were exclusively bound to high molecular weight proteins even after deoxycholate treatment.
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  • 67
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    Calcified tissue international 30 (1980), S. 27-34 
    ISSN: 1432-0827
    Keywords: Ultrastructure ; Calcium ; Cartilage ; Vesicles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The potassium pyroantimonate technique was utilized for the selective subcellular localization of calcium in the mandibular condylar cartilage of 1-day-old rats. Electron dense calcium pyroantimonate precipitates were localized principally in mitochondria and at the cell membrane of the chondrocytes. In addition, small intracellular vesicles 0.1–0.2µm in diameter were observed in proximity to the cell membrane of chondrocytes of the mid-hypertrophic zone. The results suggest that these vesicles were being extruded from the cell into the extracellular matrix. Energy-dispersive analysis by X-rays confirmed that calcium is the principal cation of the electron-dense precipitates.
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  • 68
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    Archives of gynecology and obstetrics 230 (1980), S. 123-135 
    ISSN: 1432-0711
    Keywords: Clip ; Bleier-Clip ; Tube ; Histologie ; Sterilisation ; Ultrastruktur ; Clip ; Bleier clip ; Fallopian tube ; Histology ; Sterilization ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary A bilateral salpingectomy was performed at the time of vaginal hysterectomy in a pregnant patient sterilized 20 months earlier by application of Bleier clips to the fallopian tubes. Clip application to the left tube had been incomplete. Undisturbed tissue (left tube) and clipped tissue (right tube) were examined and compared by light and scanning electron microscopy. The segment of tube fully grasped by the clip had a completely detached lining epithelium with coarse and flattened mucosa, a loose stroma, and disorganized muscular bundles. The left tubal mucosa was normal, whereas the right tube was stenosed at the site of clip placement, with rigid walls and a 0.175 mm luminal diameter. With progressively greater stenosis toward the clip site, mucosal destruction increased. Polypoidal mucosal folds were seen, as well as fibrous adhesions between mucosal folds. These observations indicate that tissue damage is extensive enough after clip application to require excision of the damaged segment of tube and microsurgical re-anastomosis for reversal of sterilization.
    Notes: Zusammenfassung Das Untersuchungsgut, über welches hier eingehend berichtet wird, stammt von einer 37jährigen Schwangeren (8. Woche), bei welcher 20 Monate zuvor eine Sterilisation mit Bleier-Clips versucht worden war. Es ergab sich eine Indikation zur Hysterektomie mit bilateraler Salpingektomie, was uns erlaubte, die gewebliche Reaktion einer Tube, an der ein Bleier-Clip korrekt saß, mit der an der kontralateralen Tube, über welche die Schwangerschaft eingetreten war, zu vergleichen. Die Präparate wurden rasterelektronenmikroskopisch und anschließend an identischen Stellen desselben Blocks lichtmikroskopisch untersucht („post-scanning histology“). In der voll gefaßten rechten Tube war das luminale Epithel streckenweise von der Unterlage abgehoben, das Faltenrelief der Mucosa distal und proximal der Clipmarke vergröbert oder abgeflacht, das subepitheliale Bindegewebe aufgelockert und die Bündel der Muscularis auseinandergedrängt. Die nur partiell mitgefaßte und daher noch ausreichend durchgängige linke Tube war zwar stenosiert, jedoch abgesehen von Schwangerschaftszeichen ohne markante Veränderung des Epithels. In der durch der korrekt sitzenden Clip verschlossenen rechten Tube verengte sich die Stenose der Clipmarke trichterförmig von proximal wie von distal, ein solider Epithelstrang war lichtmikroskopisch jedoch durchgehend nachzuweisen. Schleimhautmikropolypen und narbige Überbrückungen des Faltenreliefs in unmittelbarer Nachbarschaft des korrekt sitzenden Clips veranschaulichen, ebenso wie die narbigen Veränderungen der Tubenwand, daß eine funktionsfähige Wiederherstellung der Tubenkontinenz nach Entfernung eines zur temporären Sterilisierung applizierten Bleier-Clip kaum anders als durch eine mikrochirurgische Reanastomosierung nach Resektion der narbigen Stenose erwartet werden kann.
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  • 69
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    Calcified tissue international 31 (1980), S. 93-108 
    ISSN: 1432-0827
    Keywords: Calculus ; Ultrastructure ; Apatite ; Transmission ; Scanning
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Using transmission and scanning electron microscopy, we have studied the ultrastructure of a number of urinary calculi, mainly composed of calcium phosphate. Three fundamental kinds of calcium phosphates were detected: nonstoichiometric carbonate apatite, nonhexagonal octacalcium phosphate, and calcium-magnesium whitlockite. The influence that the organic matter, substitutions in the phosphate lattice of CO3 and Mg, and apatitic stoichiometry have on the ultrastructure of the calcium phosphate calculi has been detailed. An originating apatitic unity named U2 is assumed to be the responsible for all the different structures of calcium apatites appearing in renal calculi. On the basis of our observations, a mechanism whereby apatites grow is postulated; magnesium functions as an inhibitor for the growing mechanism.
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  • 70
    ISSN: 1432-0584
    Keywords: Rat ; Thrombocytes ; Cell volume ; Electrophoretic mobility ; Haematopoiesis ; Ratten ; Thrombozyten ; Zellvolumen ; elektrophoretische ; Beweglichkeit ; Hämatopoese
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Volumenverteilung von Rattenthrombozyten zeigt zwischen dem 5. und dem 8. Tag nach Geburt eine deutliche Zunahme im Modalvolumen. Bei rechnerischer Analyse der Kurven konnten keine deutlichen Anhaltspunkte für zwei diskrete Thrombozytenpopulationen gefunden werden. Da sich jedoch der Anstieg des Modalvolumens mit dem Beginn der Produktion einer neuen Erythrozytenpopulation deckt, und außerdem die Thrombozytenkonzentration im Blut in dieser Zeit deutlich ansteigt, können diese Veränderungen Ausdruck der Produktion einer zweiten Thrombozytenpopulation sein. Die mittlere elektrophoretische Beweglichkeit der Rattenthrombozyten fällt in den ersten drei Wochen nach Geburt nur geringfügig ab, während die der Erythrozyten im gleichen Zeitraum signifikant anstiegt.
    Notes: Summary The volume distribution curves of rat thrombocytes show a significant rise of the modal volume between days 5 and 8 after birth. No clear evidence for two distinct thrombocyte populations was obtained by computer analysis of the volume distribution curves. However, the increase of the modal volume of the platelets correlates with the production of a new erythrocyte population. In addition, the platelet concentration in the blood increases significantly during this time. These changes could indicate the production of a second thrombocyte population. The mean electrophoretic mobility of rat thrombocytes decreases only slightly during the first 3 weeks after birth, while it increases for erythrocytes significantly during the same period.
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  • 71
    ISSN: 1432-2307
    Keywords: Congenital Nephrotic Syndrome of Finnish type ; Histochemical ; Placentomegaly ; Trophoblast basement membrane alteration ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We have studied the morphological aspects of a thirty-six week gestational age placenta in the Congenital Nephrotic Syndrome of Finnish type. The study, conducted with histological, histochemical, morphometric and ultrastructural methods, demonstrates the presence of primary disorders of placentation consisting of persistent embryonic villi, arrested ramification and chorionangiomatosis. The villous development is compatible with the first-second trimester of pregnancy. Vasculo-syncytial membranes are quantitatively increased. Histochemical findings document placental immaturity further: Perls' reaction was positive for the trophoblast basement membrane (this is normally not observed beyond the second trimester), Alcian Blue positivity at pH 1 was also evident and was observed in three month gestational age placentae and in controls. Periodic Acid Silver Methenamine and Thioaldehyde Fuchsin documented abnormal thickenings of the trophoblast basement membrane. Electron microscopic observation reveals that the trophoblast basement membrane is thickened. Osmiophilic bodies are distributed throughout the trophoblast basement membrane and also within the basement membrane like material. Abundant microfibrils are present in the villous stroma. Lamination of basement membrane like material is observed in a subendothelial position. On the basis of their findings and in conjunction with the data in the literature regarding biochemical alterations of renal glomerular basement membranes in Congenital Nephrotic Syndrome Finnish type, the Authors suggest that a primitive membranopathy forms the basis for this pathological condition.
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  • 72
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    Virchows Archiv 389 (1980), S. 27-41 
    ISSN: 1432-2307
    Keywords: Chondrosarcoma ; Clear-cell chondrosarcoma ; Glucosaminoglycans ; Histochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Two cases of clear-cell chondrosarcoma located in the upper end of the right femur of men aged 30 and 40 years are reported. The roentgenologic appearances suggested a chondroblastoma. Both patients are alive, one and four years after surgical removal of the tumor. Glucosaminoglycans were studied with cationic dyes at different pH, with and without pretreatment with testicular hyaluronidase, and with the Scott technique at the light-microscopic level. Ultrastructurally, the glucosaminoglycans were studied with the high iron diamine and dialyzed iron techniques and glycogen with the PATCH-method. Light-microscopically, the tumors were characterized by clear vacuolated cells with distinct cytoplasm boundaries and scattered multinucleated giant cells of osteoclast type. Histochemical studies at the light-microscopic level indicate the presence of chondroitin 4- and 6-sulphate but no keratosulphate. Ultrastructurally, the predominant clear-cells showed features characteristic for chondroblasts. The cytoplasm showed areas lacking organelles and containing a low-density, finely granular matrix. These areas are considered to correspond to the clear cytoplasmic vacuoles seen under the light microscope. Most of the organelles were seen in the perinuclear region. The irregular tumor cells formed delicate protruding cytoplasmic extensions, which delineated intercellular spaces appearing as vacuoles under the light microscope. The benign multinucleated giant cells had an ultrastructural appearance typical of osteoclasts. Histochemical analysis at the electron-microscopic level showed the presence of sulphated glucosaminoglycans in the intercellular matrix and in association with the cytoplasmic membrane. Glycogen and non-sulphated acid glucosaminoglycans were found within the cytoplasm of the clear-cells.
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  • 73
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    Virchows Archiv 389 (1980), S. 59-77 
    ISSN: 1432-2307
    Keywords: Ethanol ; Myocardium ; Ultrastructure ; Morphometry ; Mitochondria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Male Wistar rats were fed with ethanol for 33 weeks. Ethanol was administered in a liquid diet containing 33% of the calories as ethanol. In the control group ethanol was isocalorically replaced by glucose. Light and electron microscopic investigation of the hearts did not indicate significant structural abnormalities, in contrast to the results of some other groups. Nevertheless, morphometric analysis revealed considerable quantitative changes. The number of mitochondria was remarkably reduced and the volume of an average single mitochondrion nearly doubled, whereas the volume fractions of mitochondria and myofibrils were unaltered. The analysis of the mitochondrial subcompartments indicated a slight decrease of the surface area of inner mitochondrial membranes per unit volume of mitochondria and a slight increase of the volume fraction of the mitochondrial matrix space. Myocardial cell hypertrophy or atrophy were not observed. We believe that the mitochondrial changes are the expression of an impaired biogenesis of these organelles. The increased number of capillaries in the ethanol-fed group is possibly caused by functional ethanol effects which may be partly similar to effects of chronic hypoxia. Ethanol- or acetaldehyde-induced damage of heart mitochondria may play an important role in the pathogenesis of alcoholic cardiomyopathy.
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  • 74
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    Naunyn-Schmiedeberg's archives of pharmacology 312 (1980), S. 265-270 
    ISSN: 1432-1912
    Keywords: Phyllomedusa sauvagei ; Sauvagine ; Blood pressure ; Diuresis ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. The occurrence of sauvagine, a new polypeptide from amphibian skin, and its actions on rat blood pressure and diuresis were studied. 2. Sauvagine was found to be present in the skin of all the 10 Phyllomedusa species so far studied, amounts ranging from a few micrograms to 240 μg per g fresh skin. 3. The polypeptide displayed in the rat an intense, long-lasting hypotensive action accompanied by tachycardia. Hypotension was not modified by either atropine or propranolol, excluding the participation of the autonomic nervous system in its production. Tachycardia, on the contrary, was partially inhibited by propranolol. 4. Hypotension is probably the main cause of the intense antidiuresis seen in hydrated rats following sauvagine administration. Reduction in urina volume was accompanied by a decrease in GFR and an increase in tubular Na+ reabsorption.
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  • 75
    ISSN: 1432-2013
    Keywords: d-Glucose ; Tubular Transport ; Glomerulotubular balance ; Micropuncture ; Clearance ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract d-Glucose transport in the kidney of glucose loaded rats was investigated using clearance and micropuncture techniques. The range of plasma glucose concentration in clearance experiments was 20–140 mmol·l−1 and in micropuncture experiments 17–94 mmol·l−1. 1. During hyperglycemia, the glucose concentration in endproximal tubular fluid was elevated above that in arterial plasma. At plasma concentrations above 60 mmol l−1 intratubular glucose concentration was found to be about 1.2 times higher than in plasma. 2. At endproximal puncture sites TF/Posmol was unity throughout the investigated range of hyperglycemia. 3. Proximal tubular glucose reabsorption during hyperglycemia is close to saturation which is compatible to aK m=10.8 mmol l−1 as determined previously. 4. Passive glucose permeability does not change during hyperglycemia. The permeability constant of 2.03·10−5 cm·s−1 does not differ significantly from that during normoglycemia, 1.9·10−5 cm·s−1. 5. Single nephron glomerular filtration rate (SNGFR) and fluid reabsorption in the proximal convolution (C) were significantly correlated during hyperglycemia (r=0.78,P〈0.001). Fractional volume reabsorption during hyperglycemia was decreased to 0.36 as compared to control, but during hyperglycemia it was not affected by the magnitude of the glucose plasma concentration. 6. During hyperglycemia, proximal tubular glucose reabsorption (TG) was correlated to SNGFR (r=0.64,P〈0.001). This relation became insignificant when the influence of volume reabsorption (C) is controlled for (r=0.17,P〉0.5). However, the significance of the correlation between TG and C persists when the influence of SNGFR is held constant. 7. Calculations indicate that when glucose reabsorption was doubled, et sodium transport was increased about fourfold. 8. In hyperglycemia, renal transport rate (TG), when factored by renal glomerular filtration rate (GFR) seems to be linearly related to glucose plasma concentration. Up to endproximal puncture site 25.5% and by the entire kidney 68.2% of the tubular glucose load were reabsorbed. The difference may be attributed either to glucose transport systems which are localized distal to the proximal convoluted tubules and/or to an inhomogenity of the glucose transport in the different types of nephrons.
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  • 76
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    Pflügers Archiv 385 (1980), S. 161-165 
    ISSN: 1432-2013
    Keywords: Glomerular filtration rate ; Unilateral nephrectomy ; Compensatory hypertrophy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Changes in the glomerular filtration rate (GFR) were studied in rats, 4 h to 4 weeks after unilateral nephrectomy (NX). The GFR was determined with a technique using51Cr-EDTA and a single timed blood sample. The GFR determined in this way corresponded with the GFR calculated by two compartment analysis and with the plasma levels of creatinine and urea. Increases in the GFR, compared with half the GFR of sham operated rats, were observed as early as 4 h after NX. This increase was entirely due to an increase in the GFR per gram of kidney, since no increase in kidney weight was observed at that time. After the initial increase, the GFR remained at that level during the first 48 h after NX. At 48 h a significant increase in kidney weight per 100 g body weight had taken place. The longterm changes in the GFR amounted to an increase of about 80% of that of sham operated rats after 3–4 weeks. After 4 weeks, the increase in the GFR of the remaining kidney was due to an increase in kidney weight of 35% as well as an increase in the GFR per gram of kidney of 20%. These data indicate that the increase in the GFR of the remaining kidney after unilateral NX occurs rapidly and is independent of an increase in kidney weight. Compensatory hypertrophy develops at a later stage and helps to maintain the increased function of the single remaining kidney.
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  • 77
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    Pflügers Archiv 387 (1980), S. 67-68 
    ISSN: 1432-2013
    Keywords: Hepatic vein ; Catheterization ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A procedure for catheterization of a right hepatic vein is described in the rat. The procedure is based on the observation that, when the posterior half of the body is bent to the left, a right hepatic vein is aligned with the axis of anterior vena cava and posterior vena cava. A catheter, inserted in the right jugular vein and fitted with a rectilinear mandrel, is guided into the right auricle, the suprahepatic segment of posterior vena cava and a right hepatic vein. Successful catheterization of a right hepatic vein has been obtained in 47 out of 50 animals in which the procedure has been performed.
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  • 78
    ISSN: 1432-2013
    Keywords: Rat ; Renal hypertension ; Plasma renin activity ; Water intake ; Declipping ; Reclipping ; Converting enzyme inhibitor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Application of a renal artery clip in rats with an undisturbed contralateral kidney caused a sustained increase in blood pressure and a transient rise of plasma renin activity and water intake. The response of blood pressure, plasma renin activity and water intake was augmented after reapplication of the clip to normotensive declipped rats (renal hypertensive rats, from which the clip had been removed 24 h before the reapplication). The time-course of the changes of blood pressure, plasma renin activity and water intake were similar after the initial application as after reapplication of the clip. Administration of an inhibitor (SQ 14.225) of the converting enzyme abolished the increase in blood pressure and water intake after reapplication of the clip. These data indicate a critical role of renin in the rise of blood pressure and water intake after initial application of a renal artery clip as well as after reapplication of the clip to declipped rats.
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  • 79
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    Pflügers Archiv 388 (1980), S. 165-168 
    ISSN: 1432-2013
    Keywords: Colon ; Water absorption ; Electrolyte absorption ; High protein diet ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Using an in vivo sac technique, net transport of water, Na, Cl and K was studied in the colon ascendens of rats fed either a high carbohydrate (HC) or high protein (HP) diet, since water intake is elevated in HP-rats. The ligated colon sacs were filled with isotonic Krebs-Henseleit solution. Net Na and Cl absorption rates related to 1 g intestinal dry weight were 46% and 30% higher in HP-rats compared with HC-rats. Net water absorption in HP-rats exceeded that in HC-rats by 115%. Therefore the ratio between net water absorption and net absorption of solutes was higher in HP-rats than in HC-rats, and thus the hypertonicity of the absorbate was lower in the HP-rats. There was a net secretion of K in both groups of rats to about the same extent. Experiments with22Na indicate that the increased net Na absorption in HP-rats was due to an increased unidirectional Na transport from the lumen to the blood side of the colon. The group difference in the ratio between net absorption of water and solutes might be a manifestation of regulatory mechanism controlling intestinal water absorption.
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  • 80
    ISSN: 1432-2013
    Keywords: Rat ; Micropuncture ; Tubuloglomerular feedback ; DOCA-salt treatment ; Extracellular volume
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Experiments were performed in anesthetized rats to investigate the time course of the adaptive changes in tubuloglomerular feedback reactivity and juxtaglomerular renin activity induced by DOCA and NaCl loading (isotonic saline as drinking fluid plus daily injections of 25 mg/kg DOCA). In these DOCA escaped rats we studied further the effect of acute volume depletion and repletion on the magnitude of feedback responses. A significant reduction of feedback reactivity was found on the fifth day after starting the DOCA-salt treatment with maximum depression being established after two weeks. In contrast, significant reduction of juxtaglomerular renin content required 10 days and maximum depression three weeks of DOCA-salt administration. In DOCA-salt treated animals with severely curtailed feedback responses acute volume depletion was induced by a single injection of furosemide (10 mg/kg) leading to an excretion of 0.49 ±0.17 mEq sodium and a mean decrease of body weight of 2.17±0.22% over a period of 60–70 min. Mean feedback response (expressed as percent change of early proximal flow rate caused by elevating loop of Henle flow rate from zero to 40 nl/min) was −43.9 ±4.0%, significantly greater than in the pre-depletion phase and indistinguishable from responses seen in normal control rats. Repletion of extracellular volume by infusing HCO3-Ringer solution over 20 min induced a reduction in feedback responsivity to −12.0±2.9%. Plasma and juxtaglomerular renin concentration increased with volume depletion and decreased with volume repletion, but remained considerably lower than observed in normal control rats. Our results suggest that the tubuloglomerular feedback system responds to acute alterations in extracellular volume with rapid adaptations in its reactivity which is consistent with its role in the control of sodium excretion.
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  • 81
    ISSN: 1432-2013
    Keywords: Secretin ; Vasoactive intestinal peptide ; Glucagon ; Isoproterenol ; Adenylate cyclase ; Heart ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Membrane adenylate cyclase from rat heart was activated by the two gut peptides secretin and vasoactive intestinal peptide (VIP), glucagon, and the β-adrenergic drug isoproterenol, in the presence of guanosine 5′-triphosphate (GTP). With all the stimuli tested, the optimal magnesium concentration was 5 mM, i.e. in excess over the 0.5 mM ATP substrate concentration and 0.01 mM GTP used as cofactor. Under these conditions, half-maximal adenylate cyclase activation with glucagon, secretin, and VIP was achieved at concentrations of 0.5, 0.5 and 1.0 μM, respectively. Data obtained with the secretin (7–27) fragment, a secretin antagonist, indicate that secretin and VIP acted on the same binding sites, which differed from glucagon binding sites. Structural requirements for secretin activation of cardiac adenylate cyclase were evaluated by comparing the potency and efficacy of parent peptides and synthetic analogs. The gastric inhibitory peptide GIP was inactive. When using 13 mono-or bi-substituted analogs, it appeared that amino acids in positions 1, 2, 3, 4 and 6 were of major importance while those in position 5 and 11 played a relatively minor role.
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  • 82
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    Pflügers Archiv 387 (1980), S. 121-126 
    ISSN: 1432-2013
    Keywords: Local tissuepO2 ; Hypoglycemia ; Brain cortex ; ECoG ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Oxygen supply of the brain cortex together with changes in the electrocorticogram (ECoG) were investigated during and after insulin induced hypoglycemia in 13 anaesthetized rats. Local oxygen partial pressures (pO2) on the parietal cortex were continuously measured with a multiwire surface electrode of the Clark type. During early hypoglycemia with a mean arterial glucose concentration [G]a of 2.81 (SD ±0.40) mmol/l, the local tissuepO2 did not change significantly as compared to thepO2 values recorded during the control period with a normal [G]a of 4.51 (SD±0.70) mmol/l. During severe hypoglycemia at a [G]a of 1.39 (SD±0.2) mmol/l,pO2 began to increase continuously on all 104 measuring sites, independently of changes in arterial blood pressure and ECoG. During a period of 7–18 min of isoelectricity, tissuepO2 remained elevated so long as blood pressure did not decrease. After injection of a 25% glucose solution,pO2 gradually decreased to control values within 30–60 min in most experiments. We conclude from these results that oxygen supply is generally improved during severe hypoglycemia. We assume that the increase in tissuepO2 is mainly caused by an increase in microflow. Thus, the neuronal damage occurring after severe hypoglycemia, as reported in literature, cannot primarily be caused by an oxygen deficiency.
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  • 83
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    Pflügers Archiv 384 (1980), S. 93-97 
    ISSN: 1432-2013
    Keywords: Guinea pig ; Rat ; Anesthesia ; Chronic cannulation ; Blood acid-base status
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Acid-base status of arterial blood was measured in chronically cannulated, unanesthetized, unrestrained guinea pigs. Normal values were: pH=7.444±0.032,PaCO2=35.7±4.4; HCO 3 − =24.4±2.8; BE=+0.4±2.1 (n=69) andPaO2=91.9±7.3 (n=25) (Values are mean±S.D.). Induction of light anesthesia with thiopentone caused a respiratory depression (decrease inPaO2) accompanied by respiratory acidosis (increase inPaCO2 and decrease in pH) and a development of slight metabolic acidosis (decrease in base excess and standard bicarbonate). Acid base parameters of guinea pigs are compared to those obtained from rats under identical experimental conditions.
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  • 84
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    Pflügers Archiv 386 (1980), S. 221-230 
    ISSN: 1432-2013
    Keywords: Optokinetic system ; Pretectum ; Visual vestibular convergence ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract 1) The responses of single units in the pretectum (Pt) and in the n. reticularis tegmenti pontis (NRTP) to constant velocity horizontal rotation (0.25–60 deg/s) of a large-field visual pattern were studied in immobilized, non-anesthetized DA-HAN rats. In addition, responses of Pt and NRTP neurons to pure vestibular stimuli (rotation in the dark) were studied. 2) Pt neurons showed seven response types to optokinetic stimulation (Table 1). The most frequent response (48%) consisted of a very rapid increase in firing to steady state on temporonasal motion stimulation of the contralateral eye; nasotemporal stimuli yielded no change in resting rate as did stimulation of the ipsilateral eye. The response maximum occurred at a retinal slip velocity of 1 deg/s. None of the Pt units tested responded to pure vestibular stimuli. 3) NRTP neurons — as Pt units — most frequently (43%) increased their discharge rate on temporonasal stimulation of the contralateral eye and maintained a constant resting rate during nasotemporal motion. Peak response amplitudes also occurred with retinal slip velocities of 1 deg/s. Contrary to the fast time-to-peak of the responses of Pt neurons NRTP units showed a slow rise in frequency of firing to peak response levels. 4) NRTP neurons responded to pure vestibular stimuli (horizontal angular acceleration in the dark). The vestibular responses were synergistic with those evoked in the same neurons by optokinetic stimuli. Thus, the most frequently encountered type of optokinetic response (s. above) showed a type II vestibular response. 5) Comparison of OKN and Vn optokinetic responses with those of Pt and NRTP suggests that the unidirectional-selective Pt and NRTP neurons are important links in the central optokinetic path. In addition, the NRTP may represent the site at which the retinal slip signal and the eye velocity signal converge. This convergence has been postulated in models of the system [12].
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  • 85
    ISSN: 1432-2072
    Keywords: Ethanol ; Tolerance ; 5,7-Dihydroxytryptamine ; 5-HT ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract 5,7-Dihydroxytryptamine (5,7-DHT) or the vehicle was administered once into both lateral ventricles of the rat. Desmethylimipramine (DMI) was administered IP prior to the intraventricular injection of 5,7-DHT to prevent the destruction of norepinephrine (NE) terminals. Following recovery from surgery, ethanol (5 g/kg, PO) or isocaloric sucrose was given daily for 25 days. Tests at 5-day intervals showed that chronic ethanol treatment produced tolerance to the motor impairment on the moving belt test and to hypothermic effects of ethanol. The 5,7-DHT treatment did not alter either the motor impairment or hypothermia produced by the initial dose of ethanol. However, 5,7-DHT treatment produced a 75% depletion of brain serotonin (5-HT) without altering NE concentration and retarded the development of tolerance to ethanol in both measurements. This study with a specific central depletor of 5-HT, without alteration in NE concentration, extends and supports our hypothesis that brain 5-HT modulates the development of tolerance to ethanol.
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  • 86
    ISSN: 1432-2072
    Keywords: Continuous amphetamine ; Hallucinogens ; Limb flicks ; Shakes ; Grooming ; Model psychosis ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Rats injected with LSD or mescaline show the behavioral syndrome which has been previously reported following injections of hallucinogens in higher mammals: limb flicks and whole body shakes. Although these behaviors are not elicited by acute injections of amphetamine, they are present in rats which have been pretreated for 108 h with a slow-release amphetamine pellet, given a 12h rest period, and then injected with d-amphetamine. Such pellet-pretreated animals also groom their body surface excessively. We propose that this novel syndrome which follows continuous amphetamine administration can serve as an animal model of the type of amphetamine psychosis that is produced by a similar drug regimen in humans.
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  • 87
    ISSN: 1432-2072
    Keywords: Rating scales ; Photocell activity cages ; Measurement ; Stereotypy ; d-Amphetamine ; Apomorphine ; Dopamine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A novel means of measuring and analysing behavioural effects of dopamine agonists is described and illustrated by a comparison of the effects of d-amphetamine and apomorphine in the rat. d-Amphetamine (0–15 mg/kg IP) produced significant dose- and time-dependent changes in responses such as locomotion, rearing and sniffing, but not in licking or gnawing. In contrast, apomorphine (0–5 mg/kg SC) produced significant increases in licking and gnawing, as well as in locomotion and sniffing, but no changes in rearing. The results are discussed in comparison with those obtained by other methods, such as photocell beam interruptions or stereotypy rating scales, and may be of importance in elucidating the functions of the forebrain dopamine projections.
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  • 88
    ISSN: 1432-2072
    Keywords: Diazepam ; Naloxone ; Behavioral inhibition ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The effects of naloxone on diazepam-induced release of behavior in aversive situations were investigated in rats. Naloxone (0.5 and 1 mg/kg-1) suppressed diazepam-induced eating in an unfamiliar situation and reduced (1 mg/kg-1) spontaneous food intake. Naloxone (1 mg/kg-1) canceled the increased lever pressing produced by diazepam in a conflict procedure in which one electric shock was delivered at each seventh press. Naloxone (1 mg/kg-1) failed to reverse the enhanced responding for food induced by diazepam in the presence of a signal previously paired with electric foot shocks. In this situation, naloxone alone reinforced the behavioral suppression. These results suggest that transmission mediated by opiate peptides may be involved in only some ‘disinhibitory’ effects of benzodiazepines. In addition, such a peptidergic transmission may play a role in the control of stress-induced behavioral suppression.
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  • 89
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    Urological research 8 (1980), S. 107-112 
    ISSN: 1434-0879
    Keywords: Kidney transplantation ; Rat ; Renal ischaemia ; Renal preservation ; Microsurgical technique
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A modified technique for preservation and transplantation of rat kidneys, allowing precise control of the periods of warm and cold ischaemia, is presented. The donor kidney is placed in a continuously cooled micropuncture cup during the insertion. End-to-end anastomosis of arteries and veins is performed. The technique causes negligible circulatory changes on restoration of the blood flow. Eighty-nine consecutive transplantations are analysed. Complications from the vascular anastomoses occurred in 6% (5/89). In 53 survival experiments complications from the ureteric anastomoses occurred in 9% (5/53). The methodological scatter was small, with a distinct difference in the serum creatinine course and mortality of recipients obtaining kidneys subjected to cold is chaemia for different lengths of time.
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  • 90
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    European archives of oto-rhino-laryngology and head & neck 226 (1980), S. 161-176 
    ISSN: 1434-4726
    Keywords: Otosklerose ; Histochemie ; Ultrastruktur ; Lysosome ; Oxytalanfaser ; Otosclerosis ; Histochemistry ; Ultrastructure ; Lysosomes ; Oxytalan fibres
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary In a histochemical and electron microscopical study the pathogenesis of Otosclerosis was investigated. The morphological changes in the extra- and intracellular space indicated a complex metabolic disturbance of all tissue components. The observed chondrocytic chondrolysis stressed the role of the cartilage remnants in the otic capsule as an etiological factor. There was morphological evidence of a superimposed enzymatic defect.
    Notes: Zusammenfassung In einer histochemischen und ultrastrukturellen Untersuchung werden die pathologischen Bindegewebsveränderungen bei der Otosklerose analysiert. Die Erkrankung führt zu einer komplexen Schädigung aller Bindegewebskomponenten. Es finden sich morphologische Anhalte für einen Enzymdefekt, der dem initialen pathologischen Reiz aufgelagert sein kann. Die beobachtete chondrozytäre Chondrolyse unterstreicht die Bedeutung der Knorpelreste in der otischen Kapsel als pathogenetischen Faktor der Otosklerose.
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  • 91
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    European archives of oto-rhino-laryngology and head & neck 226 (1980), S. 239-250 
    ISSN: 1434-4726
    Keywords: Enchondrale Schicht ; Labyrinthknochen ; Ultrastruktur ; Vergleichende Anatomie ; Endochondral layer ; Labyrinthine bone ; Ultrastructure ; Comparative anatomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary The endochondral layer of labyrinthine bone of dog (Canis f. intermedius Woldrich) is examined by means of light and transmission electron microscopy. The osteocytes of the fine-fibred, alamellar “embryonic skein bone” (Meyer 1927) are surrounded by a fibre-less matrix. They correspond to osteocytes in long bones. Some of them are producing microfibrils according to formation of preosseous tissue which is called “intraosseous osteogenesis” (Knese 1970). Others are characterized by signs of micropetrosis or indicate osteocytic osteolysis. In the perivascular mesenchym of some vessels giant cells are visible which according to their ultrastructural characteristics are identified as osteoclasts. The occurrence of an embryonic type of bone in endochondral layer of otic capsule throughout life is discussed considering oxygenation via perivascular canalizition as well as biomechanical aspects.
    Notes: Zusammenfassung Unseres Wissens ist dies die erste transmissionselektronenmikroskopische Untersuchung des normalen Labyrinthknochens. Hier wird die enchondrale Schicht beim Hund (Canis f. intermedius Woldrich) betrachtet, da menschliche Felsenbeine sich aufgrund postmortaler Veränderungen nicht für ultrastrukturelle Studien eignen. Im „zeitlebens embryonalen Strähnenknochen“ (Meyer 1927) sieht man Zellen, die in einem fibrillenfreien, perizellulären Hof unterschiedlicher Ausdehnung liegen. Diese entsprechen den Osteozyten in anderen Knochen. Einige dieser Zellen bilden Mikrofibrillen und sind zu einer „intraossären Osteogenese“ (Knese 1970) fähig. Andere Zellen bieten das Bild einer osteozytären Osteolyse. Auch kommt eine Mikropetrosis in nicht kanalisierten, perivaskulären Regionen vor. Im perivaskulären Mesenchym erkennt man vereinzelt Riesenzellen, die aufgrund ihrer Ultrastruktur als Osteoklasten zu bezeichnen sind. Das lebenslange Vorkommen des embryonalen Strähnenknochens in der Labyrinthkapsel wird unter Berücksichtigung biomechanischer Gesichtspunkte diskutiert. Dabei wird auch auf die perivaskuläre Kanalisierung des Strähnenknochens eingegangen.
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  • 92
    ISSN: 1432-2048
    Keywords: Boron ; Foliar nutrition ; Nuclear reactions ; Transport (boron) ; Trifolium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The growth of white clover (Trifolium repens L.) is severely inhibited by boron starvation, but a foliar treatment with boric acid can transitorily alleviate the deficiency symptoms. The 10B(n ,α)7 Li nuclear reaction has been used to study boron transport in the plant after foliar application. More than 98% of the boron supplied remained at the point where it was applied to the leaves, and less than 2% was useful to the growth of the treated plant. This small “efficient” portion of boron was quite mobile. It was distributed to the different parts of the plant, then was transferred from the oldest parts to the newly formed leaves. Physiological and agronomical implications of these data are discussed.
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  • 93
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    Psychopharmacology 68 (1980), S. 257-259 
    ISSN: 1432-2072
    Keywords: Metrazol ; Conditioned taste aversion ; Rat ; Two bottle test preference ; Saccharin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Employing a two bottle drinking procedure where an animal's preference is measured between plain water and a novel fluid, it was found that the convulsant drug Metrazol produced a conditioned taste aversion to saccharin. This finding is contrary to that of previous reports and highlights the sensitivity of the two bottle method in detecting a taste aversion.
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  • 94
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    Psychopharmacology 69 (1980), S. 183-185 
    ISSN: 1432-2072
    Keywords: DPH ; Genral activity ; Stereotypy ; Supersensitivity ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Animals were administered increasing doses of diphenylhydantoin (DPH) for 20 days. During withdrawal they were observed in an open field. The results suggest that chronic DPH administration leads to a central supersensitivity phenomenon. Possible interference of DPH with dopaminergic systems was discussed.
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  • 95
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    Archives of dermatological research 267 (1980), S. 283-290 
    ISSN: 1432-069X
    Keywords: Allergic contact dermatitis ; Infiltrating cells ; Monocytes ; Lymphocytes ; Ultrastructure ; Allergische Kontaktdermatitis ; Infiltratzellen ; Monocyten ; Lymphocyten ; Ultrastruktur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Art und Feinstruktur mononuklearer Zellen, die bei allergischer Kontaktdermatitis nach ungefähr 6 h in der Epidermis auftreten, wurden im Elektronenmikroskop untersucht. Es handelte sich um Monocyten und Lymphocyten, die in ungefähr gleicher Zahl auftraten. Die Ultrastruktur der Monocyten war die gleiche wie die normaler Monocyten im Blut. Offenbar in aktiver Bewegung, erweitern sie die intercellulären Verbindungen der Keratinocyten. Die Lymphocyten zeigten einen runden oder ovalen Kern mit einigem elektronendichten Cytoplasma, das Ribosomen und Polysomen enthielt, aber nur fallweise Mitochondrien und Golgi-Komplexe.
    Notes: Summary The kind and fine structure of mononuclear cells appearing in the epidermis at about 6 h of allergic contact dermatitis were examined by electron microscopy. They were monocytes and lymphocytes, the number being about equal. The ultrastructure of monocytes was that described for normal ones in blood, and apparently actively moving, streching the intercellular connections of the keratinocytes. Lymphocytes displayed a round or oval nucleus with some electron-dense cytoplasm which contained ribosomes and polysomes but only occasional mitochondria and Golgi complexes.
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  • 96
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    Archives of dermatological research 267 (1980), S. 275-282 
    ISSN: 1432-069X
    Keywords: Allergic contact dermatitis ; Epidermal cell changes ; Ultrastructure ; Allergische Kontaktdermatitis ; epidermale Zellveränderungen ; Ultrastruktur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Frühe epidermale Veränderungen bei allergischer Kontaktdermatitis wurden im Elektronenmikroskop untersucht. Gesunde freiwillige Testpersonen wurden mit DNCB sensibilisiert und in der Folge Kontaktreaktionen hervorgerufen. Epidermale Zellveränderungen nach 3 h waren unter anderem: Auftreten kleiner Vakuolen mit oder ohne Membran, stellenweise Erweiterung des Intercellularraums und eine Veränderung des Tonofilaments in kurze, gehäufte Bündel. Nicht sensibilisierte Haut, auf die DNCB appliziert wurde, zeigte auch kleine Vacuolen mit oder ohne Membran. Monocyten drangen in den Intercellularraum ein, der nicht ausgedehnt wurde. Die benachbarten Tonofilamente der Keratinocyten blieben normal.
    Notes: Summary Early epidermal lesions of allergic contact dermatitis were examined by electron microscopy. Normal human volunteers were sensitized to DNCB, and contact reactions were elicited sequentially. Epidermal cell changes at 3 h included: the occurrence of small vacuoles with or without membrane, focal dilatation of intercellular spaces, and the alteration of tonofilaments into short, aggregated bundles. Non-sensitized skin to which DNCB was applied also showed small vacuoles with or without membrane. Monocytes infiltrated into the intercellular spaces which were not dilated, and the neighboring tonofilaments of keratinocytes remained normal.
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  • 97
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    Neurosurgical review 3 (1980), S. 151-158 
    ISSN: 1437-2320
    Keywords: Diffuse hypertrophy of the cerebellum ; Dysplastic cerebellar gangliocytoma ; Epilepsy ; Granule cell hypertrophy ; Hamartoma of the cerebellum ; Lhermitte-Duclos disease ; Megalencephaly ; Ultrastructure ; Diffuse Hypertrophie des Kleinhirns ; Dysplastisches Kleinhirn-Gangliozytom ; Epilepsie ; Granuläre Zellhypertrophie ; Hamartom des Kleinhirns ; Lhermitte-Duclos'sche Krankheit ; Megalencephalie ; Ultrastruktur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es wird über zwei Fälle von Lhermitte-Duclos'scher Erkrankung bzw. diffuser Hypertrophie des Kleinhirns berichtet. Histopathologisch handelt es sich dabei um umschriebene Dysmorphien des Kleinhirns, die so charakteristisch sind, daß sie bei chirurgischer Exploration vom bloßen Auge erkannt werden können. Die vergröberten, hypertrophen Kleinhirnläppchen heben sich zudem durch eine unterschiedliche Färbung vom normalen Kleinhirn ab (Fig. 1). An Stelle der Körnerschicht gibt es dicht beieinanderliegende, dysplastische Ganglienzellen verschiedenen Typs (Fig. 3), die myelinisierte Axone (Fig. 7) in die dadurch stark myelinisierte Molekularschicht schicken. Die Purkinjezellschicht fehlt, die Marklamellen sind stark verschmälert. Die Läsion wird als Hamartom aufgefaßt; klinisch kann sie als Raumforderung der hinteren Schädelgrube in Erscheinung treten. Die Mehrzahl der Patienten mit diffuser Kleinhirnhypertrophie haben zusätzlich andere gehäuft vorkommende Läsionen wie Megalencephalie, Schädelund Skelettanomalien, benigne und maligne extracerebrale Tumoren u. a. m. Bei dem ersten Fall handelt es sich um einen 39jährigen Mann, der neben der diffusen Kleinhirnhypertrophie ein megalencephales Gehirn (2320 g) hatte, und an einem metastasierenden Coloncarcinom ad exitum gekommen ist. Im Alter von 34 Jahren ist eine 540 g schwere Struma entfernt worden. Die Ganglienzellnatur der dysplastischen Zellen der Körnerschicht ließ sich anhand des Nachweises von Synapsen (Fig. 6) und großen Nisslschollen (Fig. 5) elektronenmikroskopisch beweisen. Bei dem zweiten Fall handelt es sich um eine 74jährige Frau, deren Kleinhirnläsion — wie im ersten Fall — klinisch nicht in Erscheinung getreten ist. Die Aetiopathologie ist nicht bekannt. Die organoide Struktur der cerebellären Läsion, die häufige Vergesellschaftung mit Megalencephalie und anderen Mißbildungen, sowie das Vorkommen von familiären Fällen macht es wahrscheinlich, daß es sich dabei um eine Entwicklungsstörung handelt. Die Lhermitte-Duclos'sche Erkrankung ist selten. Meines Wissens sind zur Zeit insgesamt 42 Fälle bekannt geworden.
    Notes: Summary Two cases of Lhermitte-Duclos disease or diffuse hypertrophy of the cerebellum are presented. This brings the total number of such cases reported in the literature to 42. Pathologically the disease is characterized by a circumscribed cerebellar lesion consisting of thickening of the cortex with closely packed dysplastic ganglion cells in the granular layer and with large myelinated axons in the molecular layer. Purkinje cells are missing and the central white matter is greatly reduced. The first patient, a man 39 years of age, had, in association to the cerebellar lesion, a megalencephalic brain (2320 g). He had suffered from epilepsy since he was 24-years-old and died with metastasizing colon carcinoma. An electron microscopic study of the cerebellar lesion disclosed perikarya containing large amounts of rough endoplasmic reticulum, cell processes filled with coated and dense core vesicles. In addition, there were numerous enlarged myelinated axons in the molecular layer. The second patient, a woman 74 years of age, had a small area of diffuse hypertrophy of the left cerebellar hemisphere measuring one centimeter in diameter. Specific symptoms were very scant in the first case and absent in the second one indicating a very slow evolution — if any — of the disease process. The etiology and pathogenesis remain unknown. However, the organoid structure of the lesion, the frequent association of megalencephaly and other congenital abnormalities, and the occurrence of familiar cases would favor the disease being basically a developmental disorder.
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  • 98
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    Research in experimental medicine 177 (1980), S. 79-84 
    ISSN: 1433-8580
    Keywords: Mesenterico-caval shunt ; Microsurgical procedure ; Patency rate ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A microsurgical technique for mesenterico-caval shunting in the rat is described. The method results in a portal blood drainage from the upper abdominal contents whereas the blood of the mesenteric vein is shunted to the inferior caval vein. Controls were undertaken after 1 and 3 weeks, either visually or radiologically. Twenty-two of 26 surviving animals showed patency of the shunt. All animals had undisturbed blood supply to the portal stump.
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  • 99
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    Parasitology research 63 (1980), S. 33-46 
    ISSN: 1432-1955
    Keywords: Parorchis acanthus ; Redia ; Ultrastructure ; Migration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Rediae ofParorchis acanthus were examined by scanning electron microscopy and the ultrastructure of the surface related to migration through the digestive gland ofNucella lapillus. The median ventral birth papilla, ventro-lateral processes, and posterior papilliform process, of young active rediae, apparently serve to anchor the body during migration. The honeycomb-like apex of the birth papilla and ventro-lateral processes may be a strengthening device. Uniciliate sensory receptors around the mouth, on the birth papilla, and posterior terminal papilla are probably touch receptors or chemoreceptors concerned with feeding and orientation during migration. After the formation of the birth pore, and with increase in size and in the number of contained cercariae, the redia becomes less active, loses its characteristic shape, and is eventually immobile.
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  • 100
    ISSN: 1432-1955
    Keywords: Ultrastructure ; Microsporidia ; Simuliidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract During an investigation of the parasites of simuliid larvae in a defined area in Southern Germany six species of Microsporidia were found. These parasites infect larvae of six different species of Simuliidae. Using light and scanning electron microscopic techniques the microsporidians were identified asAmblyospora bracteata, Thelohania fibrata, T. varians, Pleistophora multispora, P. simulii, andP. debaisieuxi. The arrangement of membranes in the cyst as well as the surface structure of the spores are described.
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